Changes In Cholesterol Concentrations Research Articles

An in-fiber sensor for simultaneous measurement of cholesterol concentration and temperature based on SPR and MMI

In this paper, we design an in-fiber two-parameter sensor with multimode fiber (MMF)-Au film coated hollow fiber (HCF)-MMF structure, which can simultaneously excite Surface Plasmon Resonance (SPR) effect and Multimode Interference (MMI) effect. A composite material of Au nanoparticles/β-cyclodextrin (AuNPs/β-CD) is deposited on the surface of the Au film coated HCF to realize highly-sensitive measurement of cholesterol concentration. Here, the AuNPs can not only enhance the measurement sensitivity of the SPR sensor, but also increase the numbers of combination sites of β-CD and cholesterol. Then, to solve the cross-sensitivity problem between temperature and cholesterol, the glycerin is selected as a temperature-sensitive material to fill into the inner channel of the HCF, making the MMI sensor sensitive to temperature, and finally realizing the simultaneous measurement of cholesterol concentration and temperature. The experimental results demonstrate that the wavelength shift of the SPR and the MMI are 12.7 nm and 7.9 nm, respectively, when the cholesterol concentration changes from 0 to 500 nM. The temperature sensitivity of the SPR and the MMI are −0.9 nm/°C and 2.64 nm/°C, respectively, in the temperature range of 30°C–46 °C. In addition, the sensor shows good recognition ability of cholesterol molecules in serum environment, with good stability, selectivity and repeatability, and has broad application prospects in the biomedical field.

Cholesterol Regulation of Membrane Proteins Revealed by Two-Color Super-Resolution Imaging.

Cholesterol and phosphatidyl inositol 4,5-bisphosphate (PIP2) are hydrophobic molecules that regulate protein function in the plasma membrane of all cells. In this review, we discuss how changes in cholesterol concentration cause nanoscopic (<200 nm) movements of membrane proteins to regulate their function. Cholesterol is known to cluster many membrane proteins (often palmitoylated proteins) with long-chain saturated lipids. Although PIP2 is better known for gating ion channels, in this review, we will discuss a second independent function as a regulator of nanoscopic protein movement that opposes cholesterol clustering. The understanding of the movement of proteins between nanoscopic lipid domains emerged largely through the recent advent of super-resolution imaging and the establishment of two-color techniques to label lipids separate from proteins. We discuss the labeling techniques for imaging, their strengths and weakness, and how they are used to reveal novel mechanisms for an ion channel, transporter, and enzyme function. Among the mechanisms, we describe substrate and ligand presentation and their ability to activate enzymes, gate channels, and transporters rapidly and potently. Finally, we define cholesterol-regulated proteins (CRP) and discuss the role of PIP2 in opposing the regulation of cholesterol, as seen through super-resolution imaging.

The effect of cholesterol on highly curved membranes measured by nanosecond Fluorescence Correlation Spectroscopy

Small lipid vesicles (with diameter ≤100 nm) with their highly curved membranes comprise a special class of biological lipid bilayers. The mechanical properties of such membranes are critical for their function, e.g. exocytosis. Cholesterol is a near-universal regulator of membrane properties in animal cells. Yet measurements of the effect of cholesterol on the mechanical properties of membranes have remained challenging, and the interpretation of such measurements has remained a matter of debate. Here we show that nanosecond fluorescence correlation spectroscopy (FCS) can directly measure the ns-microsecond rotational correlation time (τ r) of a lipid probe in high curvature vesicles with extraordinary sensitivity. Using a home-built 4-Pi fluorescence cross-correlation spectrometer containing polarization-modulating elements, we measure the rotational correlation time (τ r) of Nile Red in neurotransmitter vesicle mimics. As the cholesterol mole fraction increases from 0 to 50%, τ r increases from 17 ± 1 to 112 ± 12 ns, indicating a viscosity change of nearly a factor of 7. These measurements are corroborated by solid-state NMR results, which show that the order parameter of the lipid acyl chains increases by about 50% for the same change in cholesterol concentration. Additionally, we measured the spectral parameters of polarity-sensitive fluorescence dyes, which provide an indirect measure of viscosity. The green/red ratio of Nile Red and the generalized polarization of Laurdan show consistent increases of 1.3× and 2.6×, respectively. Our results demonstrate that rotational FCS can directly measure the viscosity of highly curved membranes with higher sensitivity and a wider dynamic range compared to other conventional techniques. Significantly, we observe that the viscosity of neurotransmitter vesicle mimics is remarkably sensitive to their cholesterol content.

Possible Association of Cholesterol as a Biomarker in Suicide Behavior.

Suicides and suicidal behavior are major causes of mortality and morbidity in public health and are a global problem. Various authors have proposed changes in lipid metabolism (total cholesterol decrease) as a possible biological marker for suicidal behavior. The objective of this study was to review the studies that have demonstrated a relationship between serum cholesterol levels and suicidal behavior and to describe the possible pathophysiological mechanisms that associate changes in cholesterol concentration and suicidal behavior. Relevant literature related to serum cholesterol levels and suicidal behavior was identified through various database searches. The data from the existing literature present the findings that relate low cholesterol levels and possible pathophysiological mechanisms (neuroinflammation, serotonergic neurotransmission), genes related to cholesterol synthesis, pharmacological treatments that alter lipid metabolism and the possible participation in suicidal behavior. Nevertheless, future research is required to describe how serum cholesterol affects cholesterol metabolism in the CNS to establish and understand the role of cholesterol in suicidal behavior.

A combination of single nucleotide polymorphisms is associated with the interindividual variability in the blood lipid response to dietary fatty acid consumption in a randomized clinical trial

Blood lipid concentrations display high interindividual variability in response to dietary interventions, partly due to genetic factors. Existing studies have focused on single nucleotide polymorphisms (SNPs) analyzed individually, which only explain a limited fraction of the variability of these complex phenotypes. We aimed to identify combinations of SNPs associated with the variability in LDL cholesterol and triglyceride (TG) concentration changes following 5 dietary interventions. In a multicenter randomized crossover trial, 92 participants with elevated waist circumference and low HDL cholesterol concentrations consumed 5 isoenergetic diets for 4 wk: a diet rich in saturated fatty acids (SFAs) from cheese, SFA from butter, monounsaturated fatty acids (MUFAs), n-6 polyunsaturated fatty acids (PUFAs), and a diet higher in carbohydrates (CHO). The association between 22 candidate SNPs in genes involved in lipid and bile acid metabolism and transport and changes in LDL cholesterol and TG concentrations was assessed with univariate statistics followed by partial least squares regression. Endpoint LDL cholesterol concentrations were significantly different (cheese: 3.18±0.04, butter: 3.31±0.04, MUFA: 3.00±0.04, PUFA: 2.81±0.04, CHO: 3.11±0.04 mmol/L; P<0.001) while endpoint TG concentrations were not (P=0.117). Both displayed consistently elevated interindividual variability following the dietary interventions (CVs of 34.5±2.2% and 55.8±1.8%, respectively). Among the 22 candidate SNPs, only ABCA1-rs2066714 and apolipoprotein E (APOE) isoforms exhibited consistent significant effects, namely on LDL cholesterol concentrations. However, several SNPs were significantly associated with changes in LDL cholesterol and TG concentrations in a diet-specific fashion. Generated multivariate models explained from 16.0 to 33.6% of the interindividual variability in LDL cholesterol concentration changes and from 17.5 to 32.0% of that in TG concentration changes. We report combinations of SNPs associated with a significant part of the variability in LDL cholesterol and TG concentrations following dietary interventions differing in their fatty acid profiles.

Beta-cyclodextrin based reflective fiber-optic SPR sensor for highly-sensitive detection of cholesterol concentration

Abstract A fiber-optic surface plasmon resonance (SPR) cholesterol sensor is proposed and demonstrated. The sensor adopts a reflective structure and uses a gold film to excite the SPR. Through esterification reaction, the beta-cyclodextrin is fixed on the gold film of the fiber-optic sensor. When the cholesterol concentration changes, the sensitive membrane structure changes and the resonant wavelength of the SPR sensor generates a red shift, so the cholesterol concentration can be measured through monitoring the wavelength shift of the SPR resonance spectrum. Experiment results showed that when the cholesterol concentration was 0 μM–0.05 μM, the shift of the resonance wavelength was linear with the change of cholesterol concentration with high sensitivity of 156.18 nm/μM. The sensor is simple, green and sensitive, and has good potential applications in biomedicine.

Modulation of Transmembrane Domain Interactions in Neu Receptor Tyrosine Kinase by Membrane Fluidity and Cholesterol.

The activation mechanism of the ErbB family of receptors is of considerable medical interest as they are linked to a number of human cancers, including an aggressive form of breast cancer. In the rat analogue of the human ErbB2 receptor, referred to as Neu, a point mutation in the transmembrane domain (V664E) has been shown to trigger oncogenic transformation. While the structural impact of this mutation has been widely studied in the past to yield models for the active state of the Neu receptor, little is known about the impact of cholesterol on its structure. Given previous reports of the influence of cholesterol on other receptor tyrosine kinases (RTKs), as well as the modulation of lipid composition in cancer cells, we wished to investigate how cholesterol content impacts the structure of the Neu transmembrane domain. We utilized high-resolution magic angle spinning solid-state NMR to measure 13C-13C coupling of selectively labelled probe residues in the Neu transmembrane domain in lipid bilayers containing cholesterol. We observe inter-helical coupling between residues that support helix-helix interactions on both dimerization motifs reported in the literature (A661-XXX-G665 and I659-XXX-V663). We further explore how changes in cholesterol concentration alter transmembrane domain interactions and the properties and mechanics of the bilayer. We interpret our results in light of previous studies relating RTK activity to cholesterol enrichment and/or depletion, and propose a novel model to explain our data that includes the recognition and binding of cholesterol by the Neu transmembrane domain through a putative cholesterol-recognition/interaction amino acid consensus sequence.

Сравнительный анализ биохимического состава синовиальной жидкости у больных с инфекционными осложнениями после эндопротезирования коленного сустава

Introduction Biochemical parameters of synovial fluid constituents were reviewed in patients prior to total knee replacement (TKR). The diagnostic value of certain biochemical tests was identified as prognostic factors in the development of infection. Purpose Comparative biochemical analysis was performed for pathogenic microflora free synovial fluid of patients grouped according to characteristics of infectious complications prior to TKR. Material and methods Synovial fluid samples with isolated strains of Staphylососcus aureus, Klеbsiella sp. and aerobic gram-positive bacilli were excluded from the study. Total protein and its fractions, electrolytes, lipid peroxidation and catalase levels were measured in the synovial fluid. Electrolytes, lipid peroxidation and catalase were determined in the synovial fluid with exclusion of samples with identified aerobic gram-positive bacilli in bacterial culture. Results Preoperative assessment of synovial fluid showed changes in cholesterol concentration and systemic electrolyte index in TKR patients later grouped into periprosthetic infection and non-infection cases. No changes were seen in protein panel. Levels of total protein and albumin were elevated in both groups. Conclusion Our findings suggest that biochemical parameters of synovial fluid can serve as a prognostic tool for infection following TKR.

Plasma sterols and depressive symptom severity in a population-based cohort.

Convergent evidence strongly suggests major depressive disorder is heterogeneous in its etiology and clinical characteristics. Depression biomarkers hold potential for identifying etiological subtypes, improving diagnostic accuracy, predicting treatment response, and personalization of treatment. Human plasma contains numerous sterols that have not been systematically studied. Changes in cholesterol concentrations have been implicated in suicide and depression, suggesting plasma sterols may be depression biomarkers. Here, we investigated associations between plasma levels of 34 sterols (measured by mass spectrometry) and scores on the Quick Inventory of Depressive Symptomatology-Self Report (QIDS-SR16) scale in 3117 adult participants in the Dallas Heart Study, an ethnically diverse, population-based cohort. We built a random forest model using feature selection from a pool of 43 variables including demographics, general health indicators, and sterol concentrations. This model comprised 19 variables, 13 of which were sterol concentrations, and explained 15.5% of the variation in depressive symptoms. Desmosterol concentrations below the fifth percentile (1.9 ng/mL, OR 1.9, 95% CI 1.2–2.9) were significantly associated with depressive symptoms of at least moderate severity (QIDS-SR16 score ≥10.5). This is the first study reporting a novel association between plasma concentrations cholesterol precursors and depressive symptom severity.

Effect of O-methyl-β-cyclodextrin-modified magnetic nanoparticles on the uptake and extracellular level of l-glutamate in brain nerve terminals

Changes in cholesterol concentration in the plasma membrane of presynaptic nerve terminals nonspecifically modulate glutamate transport and homeostasis in the central nervous system. Reduction of the cholesterol content in isolated rat brain nerve terminals (synaptosomes) using cholesterol-depleting agents decreases the glutamate uptake and increases the extracellular level of glutamate in nerve terminals. Extraction of cholesterol from the plasma membrane and its further removal from the synaptosomes by external magnetic field can be achieved by means of magnetic nanoparticles with immobilized cholesterol-depleting agent such as O-methyl-β-cyclodextrin (MCD). A simple approach is developed for preparation of maghemite (γ-Fe2O3) nanoparticles containing chemically bonded MCD. The method is based on preparation of a silanization agent containing MCD. It is synthesized by the reaction of triethoxy(3-isocyanatopropyl)silane with MCD. Base-catalyzed silanization of superparamagnetic γ-Fe2O3 provides a relatively stable colloid product containing 48μmol of MCDg−1. MCD-modified γ-Fe2O3 nanoparticles decrease the initial rate of the uptake and accumulation of l-[14C]glutamate and increase the extracellular l-[14C]glutamate level in the preparation of nerve terminals. The effect of MCD-immobilized nanoparticles is the same as that of MCD solution; moreover, magnetic manipulation of the nanoparticles enables removal of bonded cholesterol.

The Changes of Cholesterol Concentration Is Correlated With Disease Course in Patients With Pulmonary Nontuberculous Mycobacterial Disease

The Changes of Cholesterol Concentration Is Correlated With Disease Course in Patients With Pulmonary Nontuberculous Mycobacterial Disease

A Population Pharmacokinetic/Pharmacodynamic Model Predicts Favorable HDL Cholesterol Changes Over the First 5 Years in Children Treated With Current Efavirenz-Based Regimens.

Efavirenz use is associated with changes in cholesterol concentrations, but it is unclear whether this effect is related to drug concentrations. Using efavirenz and cholesterol plasma concentrations measured in 87 antiretroviral-naive children in Thailand, we assessed indirect response models to describe the evolution of high- and low-density lipoprotein (HDL, LDL) cholesterol concentrations in relation to efavirenz plasma concentrations over time where efavirenz was assumed to either stimulate cholesterol production or inhibit its elimination. Simulations of cholesterol evolution for children with different average efavirenz concentrations (Cav ) according to their assumed status of "fast" or "slow" metabolizers of efavirenz were performed. At treatment initiation, children's median (interquartile range, IQR) age was 8 years (5 to 10), body mass index z-score 0.01 (-1.05 to 1.44), HDL 31 mg/dL (24 to 44), and LDL 83 mg/dL (69 to 100). Median (IQR) efavirenz Cav was 1.7 mg/L (1.3 to 2.1) during the period of observation. The best model describing the evolution of HDL and LDL cholesterol concentrations over time assumed that efavirenz inhibited their elimination. HDL concentrations increase over 5 years, whereas LDL concentrations increased only during the first 4 months and then returned to baseline levels afterward. Simulations predicted that, after 3 years, HDL would increase to 63 mg/dL in "fast" metabolizers and 97 mg/dL in "slow" metabolizers of efavirenz. The population pharmacokinetic-pharmacodynamic (PK-PD) model shows that favorable HDL cholesterol changes can be expected in children with current efavirenz dosing guidelines over 5 years of treatment.

Hypercholesterolemia with consumption of PFOA-laced Western diets is dependent on strain and sex of mice.

Perfluorooctanoic acid (PFOA) is a man-made surfactant with a number of industrial applications. It has a long half-life environmentally and biologically. Past studies suggest a direct relationship between plasma cholesterol and PFOA serum concentrations in humans and an inverse one in rodents fed standard rodent chow, making it difficult to examine mechanisms responsible for the potential PFOA-induced hypercholesterolemia and altered sterol metabolism. To examine dietary modification of PFOA-induced effects, C57BL/6 and BALB/c mice were fed PFOA in a fat- and cholesterol-containing diet. When fed these high fat diets, PFOA ingestion resulted in marked hypercholesterolemia in male and female C57BL/6 mice and less robust hypercholesterolemia in male BALB/c mice. The PFOA-induced hypercholesterolemia appeared to be the result of increased liver masses and altered expression of genes associated with hepatic sterol output, specifically bile acid production. mRNA levels of genes associated with sterol input were reduced only in C57BL/6 females, the mice with the greatest increase in plasma cholesterol levels. Strain-specific PFOA-induced changes in cholesterol concentrations in mammary tissues and ovaries paralleled changes in plasma cholesterol levels. mRNA levels of sterol-related genes were reduced in ovaries of C57BL/6 but not in BALB/c mice and not in mammary tissues. Our data suggest that PFOA ingestion leads to hypercholesterolemia in mice fed fat and cholesterol and effects are dependent upon the genetic background and gender of the mice with C57BL/6 female mice being most responsive to PFOA.

Sugar-Sweetened Beverage Intake Is Positively Associated with Baseline Triglyceride Concentrations, and Changes in Intake Are Inversely Associated with Changes in HDL Cholesterol over 12 Months in a Multi-Ethnic Sample of Children1–3

Background: Intake of sugar-sweetened beverages (SSBs) is linked to greater cardiometabolic risk in adults. Although longitudinal evidence is sparse among children, SSB intake reduction is targeted to reduce cardiometabolic risk factors in this group.Objective: We investigated characteristics associated with consumption of SSBs in a multi-ethnic sample of children/adolescents and measured cross-sectional and longitudinal associations between SSB intake and plasma HDL cholesterol and triglycerides (TGs) over 12 mo.Methods: In a diverse cohort of children aged 8–15 y, cross-sectional associations (n = 613) between baseline SSB intake and blood lipid concentrations and longitudinal associations (n = 380) between mean SSB intake, changes in SSB intake, and lipid changes over 12 mo were assessed with multivariable linear regression.Results: Greater SSB intake was associated with lower socioeconomic status, higher total energy intake, lower fruit/vegetable intake, and more sedentary time. In cross-sectional analysis, greater SSB intake was associated with higher plasma TG concentrations among consumers (62.4, 65.3, and 71.6 mg/dL in children who consumed >0 but <2, ≥2 but <7, and ≥7 servings/wk, respectively; P-trend: 0.03); plasma HDL cholesterol showed no cross-sectional association. In the longitudinal analysis, mean SSB intake over 12 mo was not associated with lipid changes; however, the 12-mo increase in plasma HDL-cholesterol concentration was greater among children who decreased their intake by ≥1 serving/wk (4.6 ± 0.8 mg/dL) compared with children whose intake stayed the same (2.0 ± 0.8 mg/dL) or increased (1.5 ± 0.8 mg/dL; P = 0.02).Conclusions: In a multi-ethnic sample of children, intake of SSBs was positively associated with TG concentrations among consumers, and changes in SSB intake were inversely associated with HDL cholesterol concentration changes over 12 mo. Further research in large diverse samples of children is needed to study the public health implications of reducing SSB intake among children of different racial/ethnic groups. The Daily D Health Study was registered at clinicaltrials.gov as NCT01537809.

Unraveling the mechanism of cholesterol-mediated regulation of receptor dimerization in plasma membranes in vivo

Membrane cholesterol can alter the signaling pathways of living cells. However, the process that modulates the interaction of receptor proteins is still unclear. We performed single-molecule optical tracking of ligand-induced dimerization of epidermal growth factor receptors (EGFRs) in two cancerous cell lines (HeLa and A431) and one normal endothelial cell line (MCF12A). We discovered that unliganded EGFRs typically reside in non-raft regions of the plasma membrane and can move into raft domains upon ligand binding. This ligand-induced motion could be a common behavior in live cells. We found that the amount of membrane cholesterol significantly affects the stability of EGFR dimers by manipulating the total amount of membrane cholesterol with methyl-β-cyclodextrin and the local concentration of cholesterol with nystatin. The EGFR dimers in the plasma membrane of normal cells are more sensitive to changes in the local concentration of cholesterol compared with the cancer cells. Our methodology can yield useful information for understanding cholesterol-mediated protein-protein interactions in live cells.

Correspondence between effects of dietary cholesterol versus plant sterols on plasma cholesterol responsiveness and cholesterol trafficking in healthy humans

The objective was to determine the degree of correspondence in plasma cholesterol concentration changes caused by dietary cholesterol (DC) versus plant sterols (PS) and their effects on cholesterol trafficking. A randomized, cross‐over, placebo controlled free‐living clinical trial (n=51) with 3 treatment phases of 4 week duration each separated by a 4 week washout was conducted. During each phase, participants consumed one of the three treatments containing 0.6 g DC, 2 g PS/day or a placebo after breakfast meal. Plasma lipid profile was determined and cholesterol absorption (CA) was measured by using a stable isotope [3, 4‐13C]‐labeled cholesterol administered orally. Cholesterol synthesis (CS) was assessed using plasma lathosterol as a surrogate marker. DC intake increased total cholesterol (TC) compared to placebo (0.16 mmol/L; P = 0.037) and PS (0.25 mmol/L; P = 0.005). PS intake reduced (0.20 mmol/L; P = 0.042) LDL‐C only compared to DC. Cholesterol absorption was inhibited (P = 0.0001) by PS consumption compared to placebo. Results showed that the degree of cholesterol lowering with PS intake was not in concordance with the cholesterol elevating offset caused by DC intake with respect to TC and LDL‐C. The offsets in CA and CS caused by DC and PS did not align with those of LDL‐C and TC. The large inter‐individual variability in the plasma lipid responsiveness to PS and DC intake in the population could be ascribed to the above results.

The effect of rosuvastatin on low-density lipoprotein subfractions in patients with impaired fasting glucose.

Prediabetes substantially increases cardiovascular risk. We examined the effect of rosuvastatin on the quantity and quality of low-density lipoprotein cholesterol (LDL-C) in patients with dyslipidemia having impaired fasting glucose (IFG) compared to normoglycemic patients with dyslipidemia. This was a prospective observational study including patients with dyslipidemia and IFG (IFG group, n = 49) matched with normoglycemic patients with dyslipidemia (control group, n = 64). Study participants, following dietary intervention, were prescribed rosuvastatin 10 or 20 mg/d to achieve LDL-C goals. Baseline as well as 24 weeks posttreatment changes in the serum lipid profile were evaluated. Moreover, analysis of the LDL subfraction profile was conducted using a polyacrylamide tube gel electrophoresis method. Similar effects were observed in lipid profile in both treatment groups. Patients with IFG experienced a greater decrease in the cholesterol concentration of small dense LDL particles (-65.7%, P < .001 vs baseline) compared to controls (-38.5%, P < .001 vs baseline; P = .018 vs patients with IFG). There was no significant difference in the changes of cholesterol concentration of large and buoyant LDL particles in the IFG group when compared to the control group. A greater increase in the mean LDL particle size (+1.5%, P < .001 vs baseline) was noted in the IFG group compared to the control group at 24 weeks (+0.4%, P = .028 vs baseline; P = .008 vs IFG group). Targeting dyslipidemia with rosuvastatin was associated with more favorable changes in the LDL subfraction profile in patients with IFG compared to normoglycemic ones.

Perfringolysin O as a useful tool to study human sperm physiology

To evaluate perfringolysin O, a cholesterol-dependent pore-forming cytolysin, as a tool to study several aspects of human sperm physiology. Prospective study. Basic research laboratory. Human semen samples with normal parameters obtained from healthy donors. Interaction of recombinant perfringolysin O with human spermatozoa. Assessment of perfringolysin O binding to spermatozoa, tests for acrosome and plasma membrane integrity, and acrosomal exocytosis assays. Perfringolysin O associated with human spermatozoa at 4°C. The binding was sensitive to changes in cholesterol concentrations and distribution occurring in the plasma membrane of these cells during capacitation. When perfringolysin O-treated sperm were incubated at 37°C, the plasma membrane became permeable, whereas the acrosome membrane remained intact. Permeabilized spermatozoa were able to respond to exocytic stimuli. The process was inhibited by proteins that interfere with membrane fusion, indicating that large molecules, including antibodies, were able to permeate into the spermatozoa. PFO is a useful probe to assess changes in the amount and distribution of the active sterol fraction present in the sperm plasma membrane. The toxin can be used for the efficient and selective permeabilization of this membrane, rendering a flexible experimental model suitable for studying molecular processes occurring in the sperm cytoplasm.

The effect of taurine on cholesterol metabolism

The elevated plasma cholesterol level, in particular, LDL cholesterol is regarded as an important risk factor for the development of atherosclerosis and coronary artery disease. A number of studies provide the evidence that taurine has the efficient action to reduce plasma and liver cholesterol concentrations, especially to decrease VLDL and LDL cholesterol in hypercholesterolemia animal induced by high cholesterol diet. Cholesterol lowering effect of taurine is actually involved in the regulatory mechanism of cholesterol and bile acid homeostasis that mediated by CYP7A1, which has become a biomarker for cholesterol metabolism and itself is also regulated by several factors and nuclear receptors. This review summarizes the change of cholesterol concentration in metabolism observed in feeding studies of hypercholesterolemia animal dealing with taurine, and then, addresses the possible metabolic and molecular mechanisms of cholesterol lowering effect by taurine in three aspects, cholesterol clearance from blood circulation, bioconversion of cholesterol to bile acid in liver, and excretion of cholesterol and bile acid from intestine.

Monitoring adherence to drug treatment by using change in cholesterol concentration: secondary analysis of trial data

Objective To estimate the accuracy of monitoring cholesterol concentration for detecting non-adherence to lipid lowering treatment.Design Secondary analysis of data on cholesterol concentration in the LIPID (long term intervention with...