Carbamylated lipoproteins in diabetes

Diabetic dyslipidemia is characterized by quantitative and qualitative abnormalities in lipoproteins.In addition to glycation and oxidation,carbamylation is also a post-translational modification affecting lipoproteins in diabetes.Patients with type 2 diabetes(T2D)exhibit higher levels of carbamylated low-density lipoproteins(cLDL)and high-density lipoproteins(cHDL).Accumulating evidence suggests that cLDL plays a role in atherosclerosis in diabetes.cLDL levels have been shown to predict cardiovascular events and all-cause mortality.cLDL facilitates immune cell recruitment in the vascular wall,promotes accumulation of lipids in macrophages,and contributes to endothelial dysf-unction,endothelial nitric oxide-synthase(eNOS)inactivation and endothelial repair defects.Lastly,cLDL induces thrombus formation and platelet aggregation.On the other hand,recent data have demonstrated that cHDL serum level is independently associated with all-cause and cardiovascular-related mortality in T2D patients.This relationship may be causative since the atheroprotective properties of HDL are altered after carbamylation.Thus,cHDL loses the ability to remove cholesterol from macrophages,to inhibit monocyte adhesion and recruitment,to induce eNOS activation and to inhibit apoptosis.Taken together,it seems very likely that the abnormalities in the biological functions of LDL and HDL after carbamylation contribute to atherosclerosis and to the elevated cardiovascular risk in diabetes.

Nanotechnologies meeting natural sources:Engineered lipoproteins for precise brain disease theranostics

Biological nanotechnologies have provided considerable opportunities in the management of malignancies with delicate design and negligible toxicity,from preventive and diagnostic to therapeutic fields.Lipoproteins,because of their inherent blood-brain barrier permeability and lesion-homing capability,have been identified as promising strategies for high-performance theranostics of brain diseases.However,the application of natural lipoproteins remains limited owing to insufficient accumulation and complex purification processes,which can be critical for individual therapeutics and clinical translation.To address these issues,lipoprotein-inspired nano drug-delivery systems(nano-DDSs),which have been learned from nature,have been fabricated to achieve synergistic drug delivery involving site-specific accumulation and tractable preparation with versatile physicochemical functions.In this review,the barriers in brain disease treatment,advantages of state-of-the-art lipoprotein-inspired nano-DDSs,and bio-interactions of such nano-DDSs are highlighted.Furthermore,the characteristics and advanced applications of natural lipoproteins and tailor-made lipoprotein-inspired nano-DDSs are summarized.Specifically,the key designs and current applications of lipoprotein-inspired nano-DDSs in the field of brain disease therapy are intensively discussed.Finally,the current challenges and future perspectives in the field of lipoprotein-inspired nano-DDSs combined with other vehicles,such as exosomes,cell membranes,and bacteria,are discussed.

Synthetic high-density lipoprotein(sHDL):a bioinspired nanotherapeutics for managing periapical bone inflammation

Apical periodontitis(AP)is a dental-driven condition caused by pathogens and their toxins infecting the inner portion of the tooth(i.e.,dental pulp tissue),resulting in inflammation and apical bone resorption affecting 50%of the worldwide population,with more than 15 million root canals performed annually in the United States.Current treatment involves cleaning and decontaminating the infected tissue with chemo-mechanical approaches and materials introduced years ago,such as calcium hydroxide,zinc oxide–eugenol,or even formalin products.Here,we present,for the first time,a nanotherapeutics based on using synthetic highdensity lipoprotein(sHDL)as an innovative and safe strategy to manage dental bone inflammation.sHDL application in concentrations ranging from 25μg to 100μg/mL decreases nuclear factor Kappa B(NF-κB)activation promoted by an inflammatory stimulus(lipopolysaccharide,LPS).Moreover,sHDL at 500μg/mL concentration markedly decreases in vitro osteoclastogenesis(P<0.001),and inhibits IL-1α(P=0.027),TNF-α(P=0.004),and IL-6(P<0.001)production in an inflammatory state.Notably,sHDL strongly dampens the Toll-Like Receptor signaling pathway facing LPS stimulation,mainly by downregulating at least 3-fold the pro-inflammatory genes,such as Il1b,Il1a,Il6,Ptgs2,and Tnf.In vivo,the lipoprotein nanoparticle applied after NaOCl reduced bone resorption volume to(1.3±0.05)mm^(3) and attenuated the inflammatory reaction after treatment to(1090±184)cells compared to non-treated animals that had(2.9±0.6)mm^(3)(P=0.0123)and(2443±931)cells(P=0.004),thus highlighting its promising clinical potential as an alternative therapeutic for managing dental bone inflammation.

Association and its population heterogeneities between low-density lipoprotein cholesterol and all-cause and cardiovascular mortality:A population-based cohort study

Background:The association and its population heterogeneities between low-density lipoprotein cholesterol(LDL-C)and all-cause and cardiovascular mortality remain unknown.We aimed to examine the dose-dependent associations of LDL-C levels with specific types of cardiovascular disease(CVD)mortality and heterogeneities in the associations among different population subgroups.Methods:A total of 2,968,462 participants aged 35-75 years from China Health Evaluation And risk Reduction through nationwide Teamwork(ChinaHEART)(2014-2019)were included.Cox proportional hazard models and Fine-Gray subdistribution hazard models were used to estimate associations between LDL-C categories(<70.0,70.0-99.9,100.0-129.9[reference group],130.0-159.9,160.0-189.9,and≥190.0 mg/dL)and all-cause and cause-specific mortality.Results:During a median follow-up of 3.7 years,57,391 and 23,241 deaths from all-cause and overall CVD were documented.We observed J-shaped associations between LDL-C and death from all-cause,overall CVD,coronary heart disease(CHD),and ischemic stroke,and an L-shaped association between LDL-C and hemorrhagic stroke(HS)mortality(P for non-linearity<0.001).Compared with the reference group(100.0-129.9 mg/dL),very low LDL-C levels(<70.0 mg/dL)were significantly associated with increased risk of overall CVD(hazard ratio[HR]:1.10,95%confidence interval[CI]:1.06-1.14)and HS mortality(HR:1.37,95%CI:1.29-1.45).Very high LDL-C levels(≥190.0 mg/dL)were associated with increased risk of overall CVD(HR:1.51,95%CI:1.40-1.62)and CHD mortality(HR:2.08,95%CI:1.92-2.24).The stronger associations of very low LDL-C with risk of CVD mortality were observed in individuals with older age,low or normal body mass index,low or moderate 10-year atherosclerotic CVD risk,and those without diagnosed CVD or taking statins.Stronger associations between very high LDL-C levels and all-cause and CVD mortality were observed in younger people.Conclusions:People with very low LDL-C had a higher risk of all-cause,CVD,and HS mortality;those with very high LDL-C had a higher risk of all-cause,CVD,and CHD mortality.On the basis of our findings,comprehensive health assessment is needed to evaluate cardiovascular risk and implement appropriate lipid-lowering therapy for people with very low LDL-C.

Monocyte to High-density Lipoprotein Cholesterol Ratio as a Predictor of Nonalcoholic Fatty Liver Disease in Childhood Obesity

Objective Inflammation is involved in the development and progression of nonalcoholic fatty liver disease(NAFLD).The monocyte to high-density lipoprotein cholesterol ratio(MHR)has emerged as a marker for various inflammation-related diseases.The aim of the present study was to investigate the association between the MHR and NAFLD in a population with childhood obesity.Methods Based on hepatic ultrasound,a total of 504 children with obesity(357 with NAFLD and 147 without NAFLD)were included in the study.The correlation between the MHR and NAFLD risk factors was assessed by Pearson’s and Spearman’s analyses.Multivariate stepwise logistic regression analyses were conducted to explore the association between the MHR and the risk of NAFLD.Results The MHR in patients with NAFLD was significantly greater than that in patients without NAFLD[0.52(0.44-0.67)versus 0.44(0.34-0.57),P<0.001].Multivariate stepwise logistic regression analysis demonstrated that the MHR[odds ratio(OR):1.033,95%confidence interval(CI):1.015-1.051;P<0.001]was an independent predictor of NAFLD in childhood obesity patients,as were age(OR:1.205,95%CI:1.059-1.371;P=0.005],waist circumference[OR:1.037,95%CI:1.008-1.067;P=0.012],and alanine transaminase[OR:1.067,95%CI:1.045-1.089;P<0.001].Additionally,MHR quartiles showed a significant positive association with the incidence of NAFLD after adjusting for potential confounding factors.Conclusion The present study showed that the MHR may serve as an available and useful indicator of NAFLD in individuals with childhood obesity.

Low-density lipoprotein receptor-related protein 2(LRP2)is required for lipid export in the midgut of the migratory locust,Locusta migratoria

Low-density lipoprotein receptor-related protein 2(LRP2)is a multifunctional endocytic receptor expressed in epithelial cells.In mammals,it acts as an endocytic receptor that mediates the cellular uptake of cholesterol-containing apolipoproteins to maintain lipid homeostasis.However,little is known about the role of LRP2 in lipid homeostasis in insects.In the present study,we investigated the function of LRP2 in the migratory locust Locusta migratoria(LmLRP2).The mRNA of LmLRP2 is widely distributed in various tissues,including integument,wing pads,foregut,midgut,hindgut,Malpighian tubules and fat body,and the amounts of LmLRP2 transcripts decreased gradually in the early stages and then increased in the late stages before ecdysis during the nymphal developmental stage.Fluorescence immunohistochemistry revealed that the LmLRP2 protein is mainly located in cellular membranes of the midgut and hindgut.Using RNAi to silence LmLRP2 caused molting defects in nymphs(more than 60%),and the neutral lipid was found to accumulate in the midgut and surface of the integument,but not in the fat body,of dsLmLRP2-treated nymphs.The results of a lipidomics analysis showed that the main components of lipids(diglyceride and triglyceride)were significantly increased in the midgut,but decreased in the fat body and hemolymph.Furthermore,the content of total triglyceride was significantly increased in the midgut,but markedly decreased in the fat body and hemolymph in dsLmLRP2-injected nymphs.Our results indicate that LmLRP2 is located in the cellular membranes of midgut cells,and is required for lipid export from the midgut to the hemolymphand fat body in locusts.

Initial decrease in the lipoprotein(a)level is a novel prognostic biomarker in patients with acute coronary syndrome

BACKGROUND Lipoprotein(a)[Lp(a)]is a causal risk factor for atherosclerotic cardiovascular diseases;however,its role in acute coronary syndrome(ACS)remains unclear.AIM To investigate the hypothesis that the Lp(a)levels are altered by various conditions during the acute phase of ACS,resulting in subsequent cardiovascular events.METHODS From September 2009 to May 2016,377 patients with ACS who underwent emergent coronary angiography,and 249 who completed≥1000 d of follow-up were enrolled.Lp(a)levels were measured using an isoform-independent assay at each time point from before percutaneous coronary intervention(PCI)to 48 h after PCI.The primary endpoint was the occurrence of major adverse cardiac events(MACE;cardiac death,other vascular death,ACS,and non-cardiac vascular events).RESULTS The mean circulating Lp(a)level decreased significantly from pre-PCI(0 h)to 12 h after(19.0 mg/dL to 17.8 mg/dL,P<0.001),and then increased significantly up to 48 h after(19.3 mg/dL,P<0.001).The changes from 0 to 12 h[Lp(a)Δ0-12]significantly correlated with the basal levels of creatinine[Spearman’s rank correlation coefficient(SRCC):-0.181,P<0.01]and Lp(a)(SRCC:-0.306,P<0.05).Among the tertiles classified according to Lp(a)Δ0-12,MACE was significantly more frequent in the lowest Lp(a)Δ0-12 group than in the remaining two tertile groups(66.2%vs 53.6%,P=0.034).A multivariate analysis revealed that Lp(a)Δ0-12[hazard ratio(HR):0.96,95%confidence interval(95%CI):0.92-0.99]and basal creatinine(HR:1.13,95%CI:1.05-1.22)were independent determinants of subsequent MACE.CONCLUSION Circulating Lp(a)levels in patients with ACS decreased significantly after emergent PCI,and a greater decrease was independently associated with a worse prognosis.

Overexpression of low-density lipoprotein receptor prevents neurotoxic polarization of astrocytes via inhibiting NLRP3 inflammasome activation in experimental ischemic stroke

Neurotoxic astrocytes are a promising therapeutic target for the attenuation of cerebral ischemia/reperfusion injury.Low-density lipoprotein receptor,a classic cholesterol regulatory receptor,has been found to inhibit NLR family pyrin domain containing protein 3(NLRP3)inflammasome activation in neurons following ischemic stroke and to suppress the activation of microglia and astrocytes in individuals with Alzheimer’s disease.However,little is known about the effects of low-density lipoprotein receptor on astrocytic activation in ischemic stroke.To address this issue in the present study,we examined the mechanisms by which low-density lipoprotein receptor regulates astrocytic polarization in ischemic stroke models.First,we examined low-density lipoprotein receptor expression in astrocytes via immunofluorescence staining and western blotting analysis.We observed significant downregulation of low-density lipoprotein receptor following middle cerebral artery occlusion reperfusion and oxygen-glucose deprivation/reoxygenation.Second,we induced the astrocyte-specific overexpression of low-density lipoprotein receptor using astrocyte-specific adeno-associated virus.Low-density lipoprotein receptor overexpression in astrocytes improved neurological outcomes in middle cerebral artery occlusion mice and reversed neurotoxic astrocytes to create a neuroprotective phenotype.Finally,we found that the overexpression of low-density lipoprotein receptor inhibited NLRP3 inflammasome activation in oxygen-glucose deprivation/reoxygenation injured astrocytes and that the addition of nigericin,an NLRP3 agonist,restored the neurotoxic astrocyte phenotype.These findings suggest that low-density lipoprotein receptor could inhibit the NLRP3-meidiated neurotoxic polarization of astrocytes and that increasing low-density lipoprotein receptor in astrocytes might represent a novel strategy for treating cerebral ischemic stroke.

Association between sensitivity to thyroid hormones and non-highdensity lipoprotein cholesterol levels in patients with type 2 diabetes mellitus

BACKGROUND Dyslipidemia and type 2 diabetes mellitus(T2DM)are chronic conditions with substantial public health implications.Effective management of lipid metabolism in patients with T2DM is critical.However,there has been insufficient attention given to the relationship between thyroid hormone sensitivity and dyslipidemia in the T2DM population,particularly concerning non-high-density lipoprotein cholesterol(non-HDL-C).AIM To clarify the association between thyroid hormone sensitivity and dyslipidemia in patients with T2DM.METHODS In this cross-sectional study,thyroid hormone sensitivity indices,the thyroid feedback quantile-based index(TFQI),the thyroid-stimulating hormone index(TSHI),the thyrotrophic T4 resistance index(TT4RI),and the free triiodothyronine(FT3)/free thyroxine(FT4)ratio were calculated.Logistic regression analysis was performed to determine the associations between those composite indices and non-HDL-C levels.Random forest variable importance and Shapley Additive Explanations(SHAP)summary plots were used to identify the strength and direction of the association between hyper-non-HDL-C and its major predictor.RESULTS Among the 994 participants,389(39.13%)had high non-HDL-C levels.Logistic regression analysis revealed that the risk of hyper-non-HDL-C was positively correlated with the TFQI(OR:1.584;95%CI:1.088-2.304;P=0.016),TSHI(OR:1.238;95%CI:1.034-1.482;P=0.02),and TT4RI(OR:1.075;95%CI:1.006-1.149;P=0.032)but was not significantly correlated with the FT3/FT4 ratio.The relationships between composite indices of the thyroid system and non-HDL-C levels differed according to sex.An increased risk of hyper-non-HDL-C was associated with elevated TSHI levels in men(OR:1.331;95%CI:1.003-1.766;P=0.048)but elevated TFQI levels in women(OR:2.337;95%CI:1.4-3.901;P=0.001).Among the analyzed variables,the average SHAP values were highest for TSHI,followed by TT4RI.CONCLUSION Impaired sensitivity to thyroid hormones was associated with high non-HDL-C levels in patients with T2DM.

Correlation of Helicobacter pylori infection with high-density lipoprotein cholesterol levels and pulse wave conduction velocity

Background:Helicobacter pylori(HP)is associated with several gastrointestinal diseases,including peptic ulcer diseases and gastric cancer,and non-gastrointestinal diseases such as hypertension and Alzheimer's disease.However,the relationship between HP and lipid metabolism and atherosclerosis remains unclear.This study aims to investigate the association between H.pylori infection and high-density lipoprotein cholesterol levels and pulse wave conduction velocity.Methods:This is a report of a cross-sectional study that collected data from 2,827 participants.The data collected included results of life questionnaires,laboratory tests,13C-urea breath test(13C-UBT),and pulse wave conduction velocity test.Based on the results of the 13C-UBT test,the subjects were divided into two groups:the HP-uninfected group(HP−)and the HP-infected group(HP+).The study compared the differences in HDL-C levels and brachial-ankle pulse wave velocity(baPWV)between the two groups.One-way regression analysis was used to identify potential factors affecting HDL-C levels in the study population.Multiple regression equations were presented to analyze whether HP infection was an independent risk factor for abnormal HDL-C metabolism in the population.Results:Univariate analysis demonstrated that high-density lipoprotein cholesterol(HDL-C)levels were significantly lower in the HP+group compared to the HP−group,with a mean difference ofβ=−18.1 mg/dl(95%CI:−19.3 to−17.0,P<0.001).After adjusting for all variables,the HDL-C levels remained lower in the HP+group compared to the HP-group,with a mean difference ofβ=−17.4 mg/dl(95%CI:−18.2 to−16.7,P<0.001).These findings suggest that H.pylori infection is independently associated with abnormal HDL-C metabolism.Additionally,brachial-ankle pulse wave velocity(baPWV)was higher in the HP+group than in the HP−group on both sides.On the right side,the baPWV was 1,713.4±231.4 cm/s in the HP+group compared to 1,542.8±237.5 cm/s in the HP−group(t=−18.30,P<0.001).On the left side,the baPWV was 1,743.7±238.8 cm/s in the HP+group compared to 1,562.8±256.3 cm/s in the HP−group(t=−18.23,P<0.001).These results indicate a significant association between H.pylori infection and increased arterial stiffness,as measured by baPWV.Conclusion:Helicobacter pylori infection is associated with a decrease in high-density lipoprotein cholesterol levels and an increase in pulse wave conduction velocity.

Hepatitis C virus relies on lipoproteins for its life cycle

Hepatitis C virus(HCV) infects over 150 million people worldwide. In most cases, HCV infection becomes chronic causing liver disease ranging from fibrosis to cirrhosis and hepatocellular carcinoma. Viral persistence and pathogenesis are due to the ability of HCV to deregulate specific host processes, mainly lipid metabolism and innate immunity. In particular, HCV exploits the lipoprotein machineries for almost all steps of its life cycle. The aim of this review is to summarize current knowledge concerning the interplay between HCV and lipoprotein metabolism. We discuss the role played by members of lipoproteins in HCV entry, replication and virion production.

High-density lipoproteins:an emerging target in the prevention of cardiovascular disease

High-density lipoproteins （HDLs） have been well established to protect against the development of atherosclerotic cardiovascular disease. It has become apparent that in addition to the promotion of reverse cholesterol transport, HDLs possess a number of additional functional properties that may contribute to their beneficial influence on the arterial wall. A number of exciting therapeutic strategies have been developed that target HDL and its ability to protect against the development of atherosclerotic plaque. This paper will review how the promotion of the functional properties of HDL inhibits the formation of atherosclerotic plaque and stabilises lesions in patients with established disease.

High density lipoproteins and type 2 diabetes:Emerging concepts in their relationship

Patients with type 2 diabetes mellitus(T2DM) frequently exhibit macrovascular complications of atherosclerotic cardiovascular(CV) disease. High density lipoproteins(HDL) are protective against atherosclerosis. Low levels of HDL cholesterol(HDL-C) independently contribute to CV risk. Patients with T2 DM not only exhibit low HDL-C, but also dysfunctional HDL. Furthermore, low concentration of HDL may increase the risk for the development of T2 DM through a decreased β cell survival and secretory function. In this paper, we discuss emerging concepts in the relationship of T2 DM with HDL.

Expression of Monocyte Chemoattractant Protein-1 in Monocytes and Effects of Native and Oxidized Very Low Density Lipoproteins

Monocyte chemoattractant protein-1(MCP-1), a potent chemoattractant, is thought to play an important role in migration of monocytes into atherosclerotic lesions. The present study was designed to investigate the capacity of human peripheral blood monocytes to express MCP-1 and effects of native very low density lipoprotein (VLDL) and oxidized VLDL(OX-VLDL) on the expression. The total RNA was extracted from cultured monocytes, which were exposed to VLDL and OX-VLDL, and the media conditioned by monocytes were collected. MCP-1 mRNA expression was examined by Northern blot analysis. MCP-1 protein in conditioned media was determined by using sandwich ELISA. The results showed that monocytes can express MCP-1 after a 24 h incubation at 37℃，and the expression was markedly increased by a exposure to OX-VLDL, whereas the expression was slightly increased when exposed to VLDL. It suggests that the capacity of monocytes to produce MCP-1 that recruits and activates circulating monocytes may be of considerable importance in atherogenesis, and oxidation of VLDL enhances its potential to promote atherogenesis.

Metabolism of high density lipoproteins in liver cancer

Liver plays a vital role in the production and catabolism of plasma lipoproteins. It depends on the integrity of cellular function of liver, which ensures homeostasis of lipid and lipoprotein metabolism. When liver cancer occurs these processes are impaired and high-density lipoproteins are changed.

The pleiotropic vasoprotective functions of high density lipoproteins(HDL)

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

Selective Removal of Low-Density Lipoproteins from Blood by Induced Precipitation with AAS in Vitro(Ⅰ)

1 INTRODUCTION It’s evident that high level of cholesterol in blood is associated with the formation and devel-opment of familial hypercholestrolemia(FH)and atherosclerosis(AS).In general,choles-terol in blood is mainly combined with low-density lipoproteins(LDL),very low-densitylipoproteins(VLDL)and high density lipoproteins(HDL).About 60%-80% cholesterolexists in LDL and VLDL.LDL and VLDL have been recognized as the principal

Effect of low-density lipoproteins, spermatozoa concentration and glycerol on functional and motility parameters of bull spermatozoa during storage at 4℃

An extender has been developed with low-density lipoproteins （LDLs） that eliminates the microbial risks associated with the use of whole egg yolk. The objective of this study was to assess the effects of substituting egg yolk with LDLs for use as an extender in sperm preservation at 4 ℃, as well as on spermatozoa motility, plasma membrane and acrosome integrity, at two different concentrations （80×10^6 and 240× 10^6 sperm per ml） for 8 days and to evaluate glycerol toxicity in both extenders. A total of 12 ejaculates were collected from three bulls. Spermatozoa motility was examined using computer-assisted semen analysis. Plasma membrane integrity was determined using the hypo-osmotic swelling test and acrosome integrity with the fluorescein isothiocyanate-Pisum sativum agglutinin test. The semen was subsequently divided into four aliquots and diluted with Tris-egg yolk-glycerol （TEG）, Tris-egg yolk without glycerol （TE）, LDL with glycerol （LDL＋） and LDL without glycerol （LDL-）, at 80×10^6 and 240 ×10^6sperm per ml. This study showed that the LDL＋ and LDL- extenders were more effective at preserving spermatozoa motility, plasma membrane integrity and acrosome integrity than TEG and TE （P〈0.05） during 8 days of incubation. After 3 days of incubation, a toxicity of glycerol was observed in TEG, whereas no significant difference was observed between LDL＋ and LDL-. We can therefore conclude that the LDL extender can be used to refrigerate semen at 4 ~C instead of TEG and TE at 80×10^6and 240×10^6 sperm per ml for elite bulls. This finding can be used to define a policy for the storage of high-quality bull semen.

Lipids, Lipoproteins and Apolipoproteins Abnormalities inPatients undergoing Dialysis

Twenty hemodialysis (HD) patients and 20 patients on continuous am-bulatory peritoneal dialysis (CAPD) were investigated for lipids, lipoproteins andapolipoproteins abnormalities. HD patients had elevated serum triglyceride, de-creased high-density lipoprotein cholesterol (HDL-C ) and apolipoprotein A-I(Apo A-I ), whi1e CAPD patients had elevated total cho1esterol, triglyceride,low-density lipoprotein cholesterol (LDL-C), Apolipoprotein B (Apo B), Apo B/Apo A-Iratio, and decreased HDL-C, Apo A-I. Because of the molecular sievingeffects of peritoneum, CAPD have a negative effect on these abnormalities. CAPDpatients might be at greater risk of developing coronary artery disease than HD patients who are also at increased riskas compared with normals.

ApoB-containing lipoproteins promote infectivity of chlamydial species in human hepatoma cell line

AIM:To evaluate the direct binding of two main chlamydial biovars(C.trachomatis and C.pneumoniae) to plasma lipoproteins and its effect on chlamydial infection rate in human hepatoma cell line(HepG2 cells). METHODS:Murine plasma lipoproteins were fractionated and isolated using fast-performance liquid chromatography(FPLC),spotted on nitrocellulose membrane and incubated with chlamydial suspensions. Direct binding of chlamydial particles to lipoprotein fractions has been studied using lipopolysaccharide-specific antibodies in immuno-dot blot binding assay and immunoprecipitation analysis.Immunostaining protocol as well as flow cytometry analysis have been employed to study the infectivity rate of chlamydial species in HepG2 cells. RESULTS:Elementary bodies of both C.trachomatis and C.pneumoniae bind ApoB-containing fractions of plasma lipoproteins.That binding becomes stronger when heat-denatured FPLC fractions are used, suggesting a primary role of apolipoproteins in interaction between chlamydial particle and lipoprotein. Both chlamydial biovars efficiently propagate in human hepatoma cell line-HepG2 cells even in serum free conditions forming late-stage inclusion bodies and releasing extracellular elementary bodies.Preincubation of C.trachomatis and C.pneumoniae with native ApoB-containing lipoproteins enhances the rate of chlamydial infection in HepG2 cells.CONCLUSION:A productive infection caused by C. trachomatis and C.pneumoniae may take place in human-derived hepatocytes revealing hepatic cells as possible target in chlamydial infection.Obtained results may suggest the participation of lipoprotein receptors in the mechanism of attachment and/or entry of chlamydial particles into target cells.