Phylogenetic and pathogenic characterization of lumpy skin disease virus circulating in China.

The genomic characterization of emerging pathogens is critical for unraveling their origin and tracking their dissemination. Lumpy skin disease virus (LSDV) is a rapidly emerging pathogen in Asia including China. Although the first Lumpy skin disease (LSD) outbreak was reported in 2019, the origin, transmission, and evolutionary trajectory of LSDV in China have remained obscure. The viral genome of a circulating LSDV strain in China, abbreviated LSDV/FJ/CHA/2021, was sequenced using the next-generation sequencing technique. The morphology and cytoplasmic viral factory of these LSDV isolates were observed using transmission electron microscopy. Subsequently, the genomic characterization of this LSDV isolate was systematically analyzed for the first time using the bioinformatics software. The current study revealed that several mutations in the genome of LSDV isolates circulating in China were identified using single nucleotide polymorphisms (SNPs) analysis, an instrument to evaluate for continuous adaptive evaluation of a virus. Furthermore, phylogenomic analysis was used to identify the lineage using the whole genome sequences of 44 LSDV isolates. The result revealed that the isolates from China were closely similar to that of the LSDV isolates from Vietnam, which are divided into a monophyletic lineage sub-group I. The SNPs and Simplot analysis indicate no significant occurrence of the recombinant event on the genome of LSDV isolates in China. Notably, the live virus challenge experiment demonstrated that the pathogenic characterization of this LSDV isolate belongs to a virulent strain. Collectively, we gain the first insight into the evolutionary trajectory, spatiotemporal transmission, and pathogenic characterization of circulating LSDV in China. This study provides a unique reference for risk assessment, guiding diagnostics, and prevention in epizootic and non-epizootic areas.

Triterpenic Acids Present in Hawthorn Lower Plasma Cholesterol by Inhibiting Intestinal ACAT Activity in Hamsters.

Hawthorn (Crataegus pinnatifida) is an edible fruit used in traditional Chinese medicine to lower plasma lipids. This study explored lipid-lowering compounds and underlying mechanisms of action of hawthorn. Hawthorn powder extracts inhibited acylCoA:cholesterol acyltransferase (ACAT) activity in Caco-2 cells. The inhibitory activity was positively associated with triterpenic acid (i.e., oleanolic acid (OA) and ursolic acid (UA)) contents in the extracts. Cholesterol lowering effects of hawthorn and its potential additive effect in combination with plant sterol esters (PSE) were further studied in hamsters. Animals were fed a semi-synthetic diet containing 0.08% (w/w) cholesterol (control) or the same diet supplemented with (i) 0.37% hawthorn dichloromethane extract, (ii) 0.24% PSE, (iii) hawthorn dichloromethane extract (0.37%) plus PSE (0.24%) or (iv) OA/UA mixture (0.01%) for 4 weeks. Compared to the control diet, hawthorn, PSE, hawthorn plus PSE and OA/UA significantly lowered plasma non-HDL (VLDL + LDL) cholesterol concentrations by 8%, 9%, 21% and 6% and decreased hepatic cholesterol ester content by 9%, 23%, 46% and 22%, respectively. The cholesterol lowering effects of these ingredients were conversely associated with their capacities in increasing fecal neutral sterol excretion. In conclusion, OA and UA are responsible for the cholesterol lowering effect of hawthorn by inhibiting intestinal ACAT activity. In addition, hawthorn and particularly its bioactive compounds (OA and UA) enhanced the cholesterol lowering effect of plant sterols.

The citrus flavonoids hesperidin and naringin do not affect serum cholesterol in moderately hypercholesterolemic men and women.

The citrus flavonoids hesperidin and naringin have been suggested to lower blood total (TC) and LDL-cholesterol (LDL-C) both in animal models and humans. However, the evidence from previous studies in humans is not convincing. This study evaluated the LDL-C-lowering efficacy of pure hesperidin and naringin in moderately hypercholesterolemic individuals. A total of 204 healthy men and women with a serum TC concentration of 5.0-8.0 mmol/L participated in a randomized, placebo-controlled, parallel trial with 3 groups. A 4-wk preintervention period during which participants refrained from consuming hesperidin and naringin sources preceded the intervention. During the 4-wk intervention, the participants applied the same dietary restrictions and consumed 4 capsules/d providing either placebo (cellulose) or a daily dose of 800 mg hesperidin or 500 mg naringin. Blood samples to measure serum lipids were taken on 2 consecutive days at the beginning and end of the intervention phase. One hundred ninety-four participants completed the study. They maintained their prestudy body weights (mean changes lt 0.2 kg in all groups). In all groups, the mean consumption of scheduled capsules was gt 99%. Hesperidin and naringin did not affect TC or LDL-C, with endpoint LDL-C concentrations (adjusted for baseline) of 4.00 +/- 0.04, 3.99 +/- 0.04, and 3.99 +/- 0.04 mmol/L for control, hesperidin, and naringin groups, respectively. These citrus flavonoids also did not affect serum HDL-cholesterol and triglyceride concentrations. In conclusion, pure hesperidin and naringin consumed in capsules at mealtime do not lower serum TC and LDL-C concentrations in moderately hypercholesterolemic men and women.

Evaluation of drug effects on Toxoplasma gondii nuclear and plastid DNA replication using real-time PCR.

Toxoplasma gondii Nicolle and Manceaux, 1908 is a unicellular protozoan that can infect a broad spectrum of organisms including humans. In addition to a nuclear genome, it also carries a circular DNA within a plastid-like organelle (apicoplast) and a linear genome within its mitochondria. The plastid organelle has been shown to be the target of various anti-parasitic drugs or antibiotics. To evaluate the effects of agents on the DNA replication of T. gondii, we tested six drugs (ciprofloxacin, acetylspiramycin, clindamycin, azithromycin, artemether, and sulfadiazine) on the parasite cultured in Hela cells. After drug treatment for 48 h, the parasite growth and DNA replication were evaluated and quantitated using TaqMan real-time quantitative PCR with oligonucleotide primers synthesized based on a gene from the apicoplast genome (ycf24, Genbank accession no. U87145) and a gene from the nuclear genome (uprt, Genbank accession no. U10246). Our results showed that ciprofloxacin was the most effective in inhibiting the replication of the plastid DNA after 48 h drug treatment, with a reduction of 22% in the copy number of the plastid DNA. Artemether was the most effective drug in suppressing the proliferation of tachyzoites. This study also demonstrates that real-time quantitative PCR is a simple and useful technique for monitoring parasite growth and DNA replication.

Search for Natural Compounds That Increase Apolipoprotein A-I Transcription in HepG2 Cells: Specific Attention for BRD4 Inhibitors.

Although increasing apolipoprotein A-I (apoA-I) might lower the cardiovascular disease risk, knowledge on natural compounds that elevate apoA-I transcription is limited. Therefore, the aim of this study was to discover natural compounds that increase apoA-I transcription in HepG2 cells. Since BRD4 inhibition is known to elevate apoA-I transcription, we focused on natural BRD4 inhibitors. For this, the literature was screened for compounds that might increase apoA-I and or inhibit BRD4. This resulted in list A, (apoA-I increasers with unknown BRD4 inhibitor capacity), list B (known BRD4 inhibitors that increase apoA-I), and list C (BRD4 inhibitors with unknown effect on apoA-I). These compounds were compared with the compounds in two natural compound databases. This resulted in (1) a common substructure (ethyl-benzene) in 60% of selected BRD4-inhibitors, and (2) four compounds that increased ApoA-I: hesperetin, equilenin, 9(S)-HOTrE, and cymarin. Whether these increases are regulated via BRD4 inhibition and the ethyl-benzene structure inhibits BRD4 requires further study.

Serum Concentration of Plant Sterol Oxidation Products (POP) Compared to Cholesterol Oxidation Products (COP) after Intake of Oxidized Plant Sterols: A Randomised, Placebo-Controlled, Double-Blind Dose‒Response Pilot Study.

Plant sterols (PS) are oxidized to PS oxidation products (POP). This study quantified the change in serum POP compared to cholesterol oxidation products (COP) after the intake of increasing POP doses. This was a double-blind, randomized, placebo-controlled, dose‒response pilot study with healthy individuals in four groups (15 per group). The control group received products with no added PS or POP and treatment groups received daily 20-25 g margarine with added PS (mean 3 g/d) and two cookies (~28 g) for six weeks. Cookies delivered 8.7 (low-dose), 15.2 (medium-dose), or 37.2 (high-dose) mg/d POP. Fasting serum POP and COP were measured at the baseline, days 14, 28, and 42 in all participants and days 7, 21, and 35 in a subset. Sixty individuals completed the study; 52 were included in per protocol analysis. Serum POP increased with increasing POP intake and plateaued at dose >15 mg/d. Stabilized POP concentrations were (mean ± SD) 38.9 ± 6.9, 91.0 ± 27.9, 144.4 ± 37.9 and 203.0 ± 63.7 nmol/L, for control, low-, medium-, and high-dose POP groups, respectively. For all groups, the serum COP ranged from 213 to 262 nmol/L and the average POP/COP ratio was <1. Serum POP concentrations increased non-linearly, reaching stabilized concentrations in <7 days, and remained below COP concentrations after the intake of increasing POP doses.

Oxidation of sitosterol and campesterol in foods upon cooking with liquid margarines without and with added plant sterol esters.

Plant sterol (PS) oxidation products (POP) derived from sitosterol and campesterol were measured in 15 foods cooked with liquid margarine without (control) and with added 7.5% PS. POP were analyzed using a GC-MS method. PS liquid vs. control margarine resulted in a higher median POP content per food portion (1.35mg, range 0.08-13.20mg versus 0.23mg, 0.06-0.90mg), a lower PS oxidation rate (0.63 vs. 1.29%) and lower oxidation susceptibility of sitosterol vs. campesterol. POP formation was highest in shallow-fried potatoes with PS liquid margarine (64.44mg per portion food plus residual fat). Mean relative abundances of epoxy-, 7-keto-, 7-hydroxy- and triol-PS derived from sitosterol and campesterol were 40.0, 34.4, 21.5 and 4.0% with control vs. 44.1, 23.8, 29.6 and 2.4% with PS liquid margarine. In conclusion, PS liquid margarine increased POP content in foods with a POP profile characterized by a higher ratio of epoxy- to 7-keto-derivatives.

Thermal stability of plant sterols and formation of their oxidation products in vegetable oils and margarines upon controlled heating.

Fat-based products like vegetable oils and margarines are commonly used for cooking, which may enhance oxidation of plant sterols (PS) present therein, leading to the formation of PS oxidation products (POP). The present study aims to assess the kinetics of POP formation in six different fat-based products. Vegetable oils and margarines without and with added PS (7.5-7.6% w/w) in esterified form were heated in a Petri-dish at temperatures of 150, 180 and 210°C for 8, 12 and 16min. PS and POP were analysed using GC-FID and GC-MS-SIM, respectively. Increasing PS content, temperature and heating time led to higher POP formation in all tested fat-based products. PS (either naturally occurring or added) in margarines were less susceptible to oxidation as compared to PS in vegetable oils. The susceptibility of sitosterol to oxidation was about 20% lower than that of campesterol under all the applied experimental conditions. During heating, the relative abundance of 7-keto-PS (expressed as% of total POP) decreased in all the fat-based products regardless of their PS contents, which was accompanied by an increase in the relative abundance of 7-OH-PS and 5,6-epoxy-PS, while PS-triols were fairly unchanged. In conclusion, heating time, temperature, initial PS content and the matrix of the fat-based products (vegetable oil vs. margarine) showed distinct effects on POP formation and composition of individual POP formed.

Effect of Theobromine Consumption on Serum Lipoprotein Profiles in Apparently Healthy Humans with Low HDL-Cholesterol Concentrations.

Scope: Theobromine is a major active compound in cocoa with allegedly beneficial effect on high-density-lipoprotein-cholesterol (HDL-CH). We have investigated the effect of theobromine (TB) consumption on the concentrations of triglyceride (TG) and cholesterol (CH) in various lipoprotein (LP) subclasses. Methods: In a randomized, double-blind, placebo-controlled, cross-over study, 44 apparently healthy women and men (age: 60 ± 6 years, BMI: 29 ± 3 kg/m2) with low baseline HDL-CH concentrations consumed a drink supplemented with 500 mg/d theobromine for 4 weeks. TG and CH concentrations in 15 LP subclasses were predicted from diffusion-edited 1H NMR spectra of fasting serum. Results: The LP phenotype of the subjects was characterized by low CH concentrations in the large HDL particles and high TG concentrations in large VLDL and chylomicron (CM) particles, which clearly differed from a LP phenotype of subjects with normal HDL-CH. TB only reduced CH concentrations in the LDL particles by 3.64 and 6.79%, but had no effect on TG and CH in any of the HDL, VLDL and CM subclasses. Conclusion: TB was not effective on HDL-CH in subjects with a LP phenotype characterized by low HDL-CH and high TG in VLDL.

Plasma concentrations of plant sterols: physiology and relationship with coronary heart disease.

Recently, it has been questioned whether elevated levels of circulating plant sterols increase the risk of coronary heart disease (CHD). To date, no definitive conclusions regarding such a relationship have been reached, nor have there been any studies summarizing the factors that contribute to the observed elevations in plant sterol concentrations in plasma. Thus, the purpose of this review is to systematically compare the plant sterol levels of subjects from the general population and to describe factors that contribute to the variations observed. The question of whether elevated plasma concentrations of plant sterols are associated with an increased risk of CHD was also assessed. Results indicate that the key factors accounting for variations in circulating plant sterol concentrations include: apolipoprotein E phenotypes, ATP-binding cassette transporter polymorphisms, use of statin drugs, presence of metabolic syndrome, dietary intake of plant sterols, gender, and analytical techniques used in the measurement of plant sterols in the plasma. An analysis of the studies examining the relationship between circulating levels of plant sterols and CHD risk in non-sitosterolemic populations revealed no clear associations. Furthermore, it was shown that the above-mentioned factors play an important role in determining the levels of plant sterols in plasma. Since these factors may act as potential confounders, they must be controlled for before more solid conclusions can be reached.

Phytosterol oxidation products (POP) in foods with added phytosterols and estimation of their daily intake: A literature review.

1To evaluate the content of phytosterol oxidation products (POP) of foods with added phytosterols, in total 14 studies measuring POP contents of foods with added phytosterols were systematically reviewed. In non-heated or stored foods, POP contents were low, ranging from (medians) 0.03-3.6 mg/100 g with corresponding oxidation rates of phytosterols (ORP) of 0.03-0.06%. In fat-based foods with 8% of added free plant sterols (FPS), plant sterol esters (PSE) or plant stanol esters (PAE) pan-fried at 160-200°C for 5-10 min, median POP contents were 72.0, 38.1, and 4.9 mg/100 g, respectively, with a median ORP of 0.90, 0.48, and 0.06%. Hence resistance to thermal oxidation was in the order of PAE > PSE > FPS. POP formation was highest in enriched butter followed by margarine and rapeseed oil. In margarines with 7.5-10.5% added PSE oven-heated at 140-200°C for 5-30 min, median POP content was 0.3 mg/100 g. Further heating under same temperature conditions but for 60-120 min markedly increased POP formation to 384.3 mg/100 g. Estimated daily upper POP intake was 47.7 mg/d (equivalent to 0.69 mg/kg BW/d) for foods with added PSE and 78.3 mg/d (equivalent to 1.12 mg/kg BW/d) for foods with added FPS as calculated by multiplying the advised upper daily phytosterol intake of 3 g/d with the 90% quantile values of ORP. In conclusion, heating temperature and time, chemical form of phytosterols added and the food matrix are determinants of POP formation in foods with added phytosterols, leading to an increase in POP contents. Practical applications: Phytosterol oxidation products (POP) are formed in foods containing phytosterols especially when exposed to heat treatment. This review summarising POP contents in foods with added phytosterols in their free and esterified forms reveals that heating temperature and time, the chemical form of phytosterols added and the food matrix itself are determinants of POP formation with heating temperature and time having the biggest impact. The estimated upper daily intakes of POP is 78.3 mg/d for fat-based products with added free plant sterols and 47.7 mg/d for fat-based products with added plant sterol esters. Phytosterols in foods are susceptible to oxidation to form phytosterol oxidation products (POP). This review summarizes literature data regarding POP contents of foods with added phytosterols that were exposed to storage and heat treatments.

Formation of Plant Sterol Oxidation Products in Foods during Baking and Cooking Using Margarine without and with Added Plant Sterol Esters.

Plant sterols (PS) in foods are subject to thermal oxidation to form PS oxidation products (POP). This study measured POP contents of 19 foods prepared by typical household baking and cooking methods using margarines without (control) and with 7.5% added PS (as 12.5% PS-esters, PS-margarine). Median POP contents per portion size of cooked foods were 0.57 mg (range 0.05-1.11 mg) with control margarine versus 1.42 mg (range 0.08-20.5 mg) with PS-margarine. The oxidation rate of PS (ORP) was 0.50% (median) with the PS-margarine and 3.66% with the control margarine. Using the PS-margarine, microwave-cooked codfish had the lowest POP content, with 0.08 mg per portion, while shallow-fried potatoes had the highest POP content, 20.5 mg per portion. Median POP contents in cookies, muffins, banana bread, and sponge cake baked with the control or PS-margarine were 0.12 mg (range 0.11-0.21 mg) and 0.24 mg (range 0.19-0.60 mg) per portion, with a corresponding ORP of 1.38% and 0.06%, respectively. POP contents in all the cooked and baked foods did not exceed 20.5 mg per typical portion size. A wide variation in the distribution of individual POP among different foods existed, with 7-keto-PS and 5,6-epoxy-PS being the major oxidation products.

Wheat germ policosanol failed to lower plasma cholesterol in subjects with normal to mildly elevated cholesterol concentrations.

Sugar cane policosanol, a mixture of long-chain primary alcohols (approximately 67% as octacosanol), has been reported to lower plasma low-density lipoprotein (LDL)-cholesterol. We investigated the effect of wheat germ policosanol (WGP) on plasma lipid profiles in 58 adults (30 men and 28 women, aged 49 +/- 11 years) with normal to mildly elevated plasma cholesterol concentrations in a double-blind, randomized, parallel placebo-controlled study. Subjects consumed chocolate pellets with or without 20 mg/d WGP for 4 weeks. Plasma lipid concentrations, routine blood chemistry and hematology were determined at the start and the end of the study. The initial plasma total, LDL-cholesterol, high-density lipoprotein (HDL)-cholesterol, and triacylglycerol concentrations in the WGP and the control groups were identical. Over the 4 weeks, neither the WGP nor the control treatment significantly changed plasma total cholesterol, LDL- and HDL-cholesterol, or triacylglycerol concentrations when compared to baseline values. In addition, there was no significant difference in plasma lipid profiles between the WGP and the control groups at the end of the study. WGP did not result in any adverse effects as indicated by plasma activities of L-gamma-glutamyltransferase (gamma-GT), ALT, AST, bilirubin concentrations, and blood cell profiles. Chemical analysis showed that WGP consists of 8% hexacosanol, 67% octacosanol, 12% triacosanol, and 13% other long-chain alcohols, which is similar to the composition of sugar cane policosanol. In conclusion, WGP at 20 mg/d had no beneficial effects on blood lipid profiles. It therefore seems unlikely that the long chain (C24-34) alcohols have any cholesterol-lowering activity.

Consumption of plant sterol-enriched foods and effects on plasma plant sterol concentrations--a meta-analysis of randomized controlled studies.

OBJECTIVE: Intake of plant sterol (PS)-enriched foods effectively lowers plasma total- and LDL-cholesterol concentrations while increasing plasma PS concentrations. The magnitude of this increase has not been systematically assessed. This study aimed to investigate the effect of PS-enriched foods on plasma PS concentrations by performing a meta-analysis of randomized controlled studies. METHODS: Published PS intervention studies reporting plasma PS concentrations were searched through June 2012. Studies were selected that fulfilled pre-defined in- and exclusion criteria. Data were extracted, particularly on campesterol, sitosterol, total- and LDL-cholesterol. Random-effects models were used to calculate net effects while weighing each study by the inverse of its variance. Potential sources of heterogeneity were investigated. RESULTS: The meta-analysis included data from 41 studies (55 strata) with in total 2084 subjects. The average dose of PS from enriched foods was 1.6 g/d (range: 0.3-3.2 g/d). Plasma sitosterol and campesterol concentrations were increased by on average 2.24 µmol/L (31%) and 5.00 µmol/L (37%), respectively, compared to control. Total- and LDL-cholesterol were reduced by on average 0.36 mmol/L (5.9%) and 0.33 mmol/L (8.5%), respectively. The increase in sitosterol and campesterol was impacted by the dose of PS, the baseline PS concentration and the PS composition of the test products. In the highest PS dose category (2.0-3.2 g/d), increases in sitosterol and campesterol were on average 3.56 and 7.64 µmol/L, respectively. CONCLUSION: Intake of PS-enriched foods increases plasma sitosterol and campesterol concentrations. However, total PS remain below 1% of total sterols circulating in the blood.

A reappraisal of the mechanism by which plant sterols promote neutral sterol loss in mice.

UNLABELLED: Dietary plant sterols (PS) reduce serum total and LDL-cholesterol in hyperlipidemic animal models and in humans. This hypocholesterolemic effect is generally ascribed to inhibition of cholesterol absorption. However, whether this effect fully explains the reported strong induction of neutral sterol excretion upon plant sterol feeding is not known. Recent data demonstrate that the intestine directly mediates plasma cholesterol excretion into feces, i.e., without involvement of the hepato-biliary route. OBJECTIVE: Aim of this study was to determine whether stimulation of fecal neutral sterol loss during PS feeding is (partly) explained by increased intestinal cholesterol excretion and to assess the role of the cholesterol transporter Abcg5/Abcg8 herein. METHODS AND RESULTS: Wild-type mice were fed a control diet or diets enriched with increasing amounts of PS (1%, 2%, 4% or 8%, wt/wt) for two weeks. In addition, Abcg5(-/-) mice were fed either control or 8% PS diet. PS feeding resulted in a dose-dependent decrease of fractional cholesterol absorption (∼2-7-fold reduction) in wild-type mice and ∼80% reduction in Abcg5(-/-) mice. Furthermore, PS feeding led to a strong, dose-independent induction of neutral sterol excretion (3.4-fold in wild-types and 2.7-fold in Abcg5(-/-) mice) without changes in biliary cholesterol secretion. It was calculated that PS feeding stimulated intestinal cholesterol excretion by ∼500% in wild-type mice and by ∼250% in Abcg5(-/-). CONCLUSIONS: Our data indicate that in mice the cholesterol-lowering effects of PS are to a large extent attributable to stimulation of intestinal, non-bile derived, cholesterol excretion. The Abcg5/Abcg8 heterodimer is involved in facilitating this PS-induced flux of cholesterol.

Molecular structures of citrus flavonoids determine their effects on lipid metabolism in HepG2 cells by primarily suppressing apoB secretion.

This study investigated the underlying mechanisms of action for blood lipid lowering effects of citrus flavonoids and their methoxylated analogues (n = 19; dose range: 0-100 µM) in HepG2 cells. Cholesterol (CH) and triglyceride (TG) syntheses were assessed by measuring the incorporation of (14)C-acetate and (14)C-glycerol, respectively, whereas apoB secretion was determined by ELISA. Results show that two polymethoxylated citrus flavonoids (PMFs), tangeretin and nobiletin, potently inhibited apoB secretion (IC(50) = 13 and 29 µM, respectively) and modestly inhibited CH synthesis (IC(50) = 49 and 68 µM) and TG synthesis (IC(50) = 14 and 73 µM), without effecting LDL-receptor activity. Other PMFs (e.g., sinensetin) and non-PMFs (e.g., hesperetin and naringenin) had only weak effects on CH and TG syntheses and apoB secretion (IC(50) > 100 µM). The structure-activity analysis indicated that a fully methoxylated A-ring of the flavonoid structure was associated with a potent inhibitory activity on hepatic apoB secretion. In conclusion, this study using HepG2 cells indicates that citrus flavonoids with a fully methoxylated A-ring may lower blood CH and TG concentrations primarily by suppressing hepatic apoB secretion as a main underlying mode of action.

The experimental development of Ophiotaenia monnigi Fuhrmann, 1924 in Cyclops leuckarti.

Cyclops leuckarti and C. prasinus can serve as the intermediate hosts of Ophiotaenia monnigi, Fuhrmann, 1924. From the hexacanth, the parasite developed to a mature procercoid larva without a cercomere, although it appeared in the development processes. At the two-part development stage, all the hooks transferred to the cercomere, and it dropped off in the latest time of the larval developing. In the development, a coelom presented in the front part as well as in the cercomere. An apical appeared, and two pairs of gland cells were found after the sucker. The whole developmental course took more than 11 days, and it was even longer in the host, C. prasinus, in which the parasite larva developed slower.

Reduction of cholesterol absorption by dietary plant sterols and stanols in mice is independent of the Abcg5/8 transporter.

Dietary supplementation with plant sterols, stanols, and their esters reduces intestinal cholesterol absorption, thus lowering plasma LDL cholesterol concentration in humans. It was suggested that these beneficial effects are attributable in part to induction of genes involved in intestinal cholesterol transport, e.g., Abcg5 and Abcg8, via the liver X receptor (LXR), but direct proof is lacking. Male C57BL/6J mice were fed a purified diet (control), diets containing cholesterol (0.12 g/100 g) only, or in combination with either plant sterols or stanols (0.5 g/100 g) for 4 wk. Plant sterols and stanols dramatically increased neutral fecal sterol excretion (2.2 and 1.4-fold, respectively, compared with cholesterol-fed mice; P < 0.05). Cholesterol and cholesterol ester concentrations were higher in livers of mice fed cholesterol compared with controls (+135% and +925%; P < 0.05). Plant sterols and stanols completely prevented cholesterol accumulation as well as induction of LXR target genes in liver. Feeding plant sterols and stanols did not alter intestinal expression of Abcg5, Abcg8, or other LXR target genes nor of Npc1l1. Fractional cholesterol absorption in Abcg5-/- mice was reduced to the same extent by dietary plant sterols (49%) as in wild-type littermates (44%). Plant sterol and stanol-induced reduction of cholesterol absorption in mice is not associated with upregulation of intestinal LXR target genes nor is it influenced by Abcg5-deficiency. Our data indicate that dietary plant sterols and stanols inhibit cholesterol absorption within the intestinal lumen independently of LXR.

Soy protein enhances the cholesterol-lowering effect of plant sterol esters in cholesterol-fed hamsters.

This study aimed to investigate whether the combination of plant sterol esters (PSE) with soy protein or soy isoflavones may have extra cholesterol-lowering effects. Male hamsters (n=20/group) were fed diets containing (g/100 g diet) (A) 20 casein (control), (B) 0.24 PSE, (C) 20 intact soy protein (replacing casein), (D) 0.02 soy isoflavones, (E) 0.24 PSE plus 20 soy protein (replacing casein), or (F) 0.24 PSE plus 0.02 soy isoflavones, for 5 wk. All diets contained 0.08 g cholesterol/100 g diet. Compared with the control diet, the PSE and soy protein diets significantly lowered the plasma total cholesterol concentration by 13% (P<0.05) and 9% (P<0.05), respectively, whereas the isoflavone diet (D) had no effect. The combination of PSE and soy protein (diet E) decreased plasma total cholesterol by 26% (P<0.05). The decrease in plasma cholesterol concentration was mainly in the non-HDL fraction. In addition, the combination of PSE and soy protein significantly decreased plasma triacylglycerol concentration (37%, P<0.05) and reduced cholesterol accumulation in the liver. The abundance of hepatic LDL-receptors was not influenced by any of the test diets. PSE selectively increased fecal excretion of neutral sterols by 190% (P<0.05), whereas soy protein increased fecal excretion of neutral sterols and bile acids by 66% (P<0.05) and 130% (P<0.05), respectively. The combination of PSE and soy protein increased the fecal excretion of neutral sterols and bile acids compared with PSE and soy protein alone. In conclusion, the combination of PSE and soy protein more dramatically lowers plasma lipids than the individual ingredients.