Reduce Blood Cholesterol Levels Research Articles

New insight into the catalytic properties of bile salt hydrolase

Abstract Bile salt hydrolase (BSH), the enzyme deconjugating bile potentially plays an important role in reduction of blood cholesterol level. BSH enzymes from various sources differ in characteristics, substrates preference and specific catalytic activity. In this study, two BSH enzymes (BSH1 and BSH2) from Lactobacillus salivarius were heterologously expressed and purified. Both of them were characterized as homotetramer according to their molecular weight from size exclusion chromatograph. BSH1 showed a broad pH optimum over the range from 5.5 to 7.0, while a narrower range of pH optimum from 5.5 to 6.0 for BSH2 was detected. The enzymatic kinetics of the purified BSH1 and BSH2 have demonstrated BSH enzymes from bacteria were allosteric enzymes, and have also revealed their striking differences in positive cooperativity, catalytic efficiency and substrate preference for the first time. In contrast to the enzymatic reactions of BSH in the absence of dithiothreitol, the kinetics curves of BSH1 and BSH2 were similar to hyperbolic forms of Michaelis–Menten kinetics in the presence of dithiothreitol.

Shiitake Mushroom: A Tool of Medicine

Medicinal mushrooms have an established history of use in traditional oriental therapies. Contemporary research has validated and documented much of the ancient knowledge. Over the last three decades, the interdisciplinary fields of science that study medicinal mushrooms has sprung up and has increasingly demonstrated the potent and unique properties of compounds extracted from a range of species. Currently, the field is being developed into a very fruitful area. Modern clinical practice in Japan, China, Korea and other Asian countries rely on mushroom-derived preparations.Mushrooms have been studied for nutritional and medical purposes for its various potential anti-tumoral and immunomodulatory componests like polysaccharides that have been identified. For medical purposes, mushrooms have been consumed to prevent cancer and cardiac diseases, to improve blood circulation and to reduce blood cholesterol level. Some of these mushrooms have also been used for the treatment of physical and emotional stress, osteoporosis, gastric ulcers and chronic hepatitis, for the improvement of the quality of life of patients with diabetes and especially for the stimulation of immunity.Shiitake has a history of medicinal uses. The mushroom is used as anticarcinogenic, antiinflammatory, antioxidant, antifungal, antibacterial, antiviral as well as antithrombotic in cardiovascular disorders. This article has been written to throw some light on Shiitake mushroom which has many nutritional values. Many Shiitake preparations came in market containing the active ingredients which can replace many other marketed synthetic medicines and may prove to have promising results with fewer side effects. DOI: http://dx.doi.org/10.3329/bjmb.v5i1.13428 Bangladesh J Med Biochem 2012; 5(1): 24-32

New Bioactive Metabolites from a Crown Gall Induced on an Eucalyptus tereticornis Sm. Tree

Applying a bioactivity-guided isolation strategy for the ethanolic extract of crown gall tumours induced on an Eucalyptus tereticornis tree, two new compounds in addition to a known one were isolated. The new compounds were identified as an amino acid derivative named 1-ethyl-6-(1'-methyl-1'-phenylethyl) piperidin-2-one (1) and a lanostane tetracyclic triterpene named 3beta-hydroxy-24-methyllanosta-8,17(20),24(28)-trien-22-oic acid (2), together with stigmasterol-3-O-glucoside (3). The three compounds exhibited significant cytotoxic activity against two human cell lines, breast (MCF7) and colon (HCT116), with IC50 values of 1.01, 1.54, and 2.15 microg/ml, respectively, against MCF7 and 3.49, 3.83, and 3.39 microg/ ml, respectively, against HCT116. Furthermore, in rats elevated levels of blood cholesterol, triglycerides, and low-density lipoprotein (LDLc) were significantly reduced, while the level of high-density lipoprotein (HDLc) was significantly increased by administration of the ethanolic extract as well as of 3. These results support a correlation between the reduction of blood cholesterol levels and improvement of colorectal cancer.

Effect of Chlorella vulgaris on serum cholesterol‐regulation in healthy subjects and hypercholesterolemia

Recently, patients with hyperlipidemia including hypercholesterolemia have increased steadily as dietary habit has been changed to western style based on high‐fat diet. Since hypercholesterolemia can develop serious cardiovascular diseases such as myocardial infarction, stroke and atherosclerosis, studies to prevent and treat this have been consistently reported. Chlorella contains a variety of nutrients such as chlorophyll, vegetable protein, essential amino acids, vitamins and dietary fiber. And its function has been approved in the aspects of its antioxidant capacity and enhancement of immune function. In the previous study, cholesterol level reducing effect has been confirmed in animal.Therefore, this study aimed to confirm that ingestion of chlorella for normal subjects interferes with the absorption of cholesterol coming from high cholesterol diet and lowers the blood cholesterol level. Additionally, it aimed to confirm the reduction of blood cholesterol level before and after ingestion of chlorella for patients with hypercholesterolemia. This study is a randomized, parallel‐group, double‐blind, placebo‐controlled trial.Besides cholesterol level, in order to confirm the extent of systemic absorption of carotenoids, the major active component of chlorella, we analyzed the level of lutein, zeaxanthin, alpha‐carotene, beta‐carotene, lycopene by HPLC in the serum before and after ingestion of chlorella.

Cholesterol-Lowering Probiotics as Potential Biotherapeutics for Metabolic Diseases

Cardiovascular diseases are one of the major causes of deaths in adults in the western world. Elevated levels of certain blood lipids have been reported to be the principal cause of cardiovascular disease and other disabilities in developed countries. Several animal and clinical trials have shown a positive association between cholesterol levels and the risks of coronary heart disease. Current dietary strategies for the prevention of cardiovascular disease advocate adherence to low-fat/low-saturated-fat diets. Although there is no doubt that, in experimental conditions, low-fat diets offer an effective means of reducing blood cholesterol concentrations on a population basis, these appear to be less effective, largely due to poor compliance, attributed to low palatability and acceptability of these diets to the consumers. Due to the low consumer compliance, attempts have been made to identify other dietary components that can reduce blood cholesterol levels. Supplementation of diet with fermented dairy products or lactic acid bacteria containing dairy products has shown the potential to reduce serum cholesterol levels. Various approaches have been used to alleviate this issue, including the use of probiotics, especially Bifidobacterium spp. and Lactobacillus spp.. Probiotics, the living microorganisms that confer health benefits on the host when administered in adequate amounts, have received much attention on their proclaimed health benefits which include improvement in lactose intolerance, increase in natural resistance to infectious disease in gastrointestinal tract, suppression of cancer, antidiabetic, reduction in serum cholesterol level, and improved digestion. In addition, there are numerous reports on cholesterol removal ability of probiotics and their hypocholesterolemic effects. Several possible mechanisms for cholesterol removal by probiotics are assimilation of cholesterol by growing cells, binding of cholesterol to cellular surface, incorporation of cholesterol into the cellular membrane, deconjugation of bile via bile salt hydrolase, coprecipitation of cholesterol with deconjugated bile, binding action of bile by fibre, and production of short-chain fatty acids by oligosaccharides. The present paper reviews the mechanisms of action of anti-cholesterolemic potential of probiotic microorganisms and probiotic food products, with the aim of lowering the risks of cardiovascular and coronary heart diseases.

Combination of fluvastatin and losartan relieves atherosclerosis and macrophage infiltration in atherosclerotic plaques in rabbits

To investigate whether the combination of fluvastatin and losartan synergistically relieve atherosclerosis and plaque inflammation induced by a high-cholesterol diet in rabbits. Atherosclerosis was induced with a high-cholesterol diet for 3 months in 36 New Zealand white rabbits. The animals were randomly divided into model group, fluvastatin (10 mg·kg(-1)·d(-1)) group, losartan (25 mg·kg(-1)·d(-1)) group, and fluvastatin plus losartan group. After the 16-week treatments, the blood samples the animals were collected, and the thoracic aortas were examined immunohistochemically. The mRNA and protein expression levels of monocyte chemotactic protein-1 (MCP-1) were measured using RT-PCR and Western blot. Compared to the treatment with losartan or fluvastatin alone, the combined treatment did not produce higher efficacy in reduction of blood cholesterol level. However, the combination did synergistically decrease the intimal and media thickness of thoracic aortas with significantly reduced macrophage infiltration and MCP-1 expression in the plaques. The combined treatment with losartan and fluvastatin significantly inhibited atherosclerotic progress and reduced inflammation associated with atherosclerotic plaques.

The influence of aqueous extract of roselle (Hibiscus sabdariffa) calyx on blood cholesterol level and body weight in rats

Marsalina M, Samigun, Hardjanti ES. 2011. The influence of aqueous extract of roselle (Hibiscus sabdariffa) calyx on blood cholesterol level and body weight in rats. Biofarmasi 9: 43-49. This study aimed to investigate the influence of aqueous extract of roselle calyx on blood cholesterol level and body weight in rats. This experimental research was arranged as a pre and post-test controlled group design. Thirty Sprague-Dawley rats, with 3 months of age and 250 g in average weight, were used as an animal model. Those rats were grouped equally into five groups, i.e. negative control (aquadest), positive control (0.26 mg lovastatin/200 g body weight of rats/2 mL), the first dose of aqueous extract of roselle calyx (65 mg/200 g/2 mL), the second dose of aqueous extract of roselle calyx (130 mg/200 g/2 mL), and the third dose of aqueous extract of roselle calyx (195 mg/200 g/2 mL). The measurement of rat blood cholesterol level was conducted before and after treatment, while the rat body weight was measured once a week. The result of this study was analyzed by using one-way ANOVA statistical test. The one-way ANOVA statistical test showed no significant difference on reducing blood cholesterol level with p=0.327 (p>0.05) and body weight in rat with p=0.154, p=0.214, and p=0.938 (p>0.05). This study concluded that the aqueous extract of roselle calyx has no influence on lowering blood cholesterol level and body weight in rats.

Statins alleviate experimental nerve injury-induced neuropathic pain

The statins are a well-established class of drugs that lower plasma cholesterol levels by inhibiting HMG-CoA (3-hydroxy-3-methyl-glutaryl-coenzyme A) reductase. They are widely used for the treatment of hypercholesterolemia and for the prevention of coronary heart disease. Recent studies suggest that statins have anti-inflammatory effects beyond their lipid-lowering properties. We sought to investigate whether statins could affect neuropathic pain by mediating nerve injury-associated inflammatory responses. The effects of hydrophilic rosuvastatin and lipophilic simvastatin were examined in the mouse partial sciatic nerve ligation model. Systemic daily administration of either statin from days 0 to 14 completely prevented the development of mechanical allodynia and thermal hyperalgesia. When administered from days 8 to 14 after injury, both statins dose-dependently reduced established hypersensitivity. After treatment, the effects of the statins were washed out within 2 to 7 days, depending on dose. Effects of both statins in alleviating mechanical allodynia were further confirmed in a different injury-associated neuropathic pain model, mental nerve chronic constriction, in rats. Both statins were able to abolish interleukin-1β expression in sciatic nerve triggered by nerve ligation. Additionally, quantitative analysis with Iba-1 and glial fibrillary acid protein immunoreactivity demonstrated that rosuvastatin and simvastatin significantly reduced the spinal microglial and astrocyte activation produced by sciatic nerve injury. The increase of interleukin-1β mRNA in the ipsilateral side of spinal cords was also reduced by the treatment of either statin. We identified a potential new application of statins in the treatment of neuropathic pain. The pain-alleviating effects of statins are likely attributable to their immunomodulatory effects. Statins, which are typically used to reduce blood cholesterol levels, could potentially have beneficial effects in the treatment of neuropathic pain.

A Modelling Approach to Estimate the Level and Molecular Weight Distribution of β-Glucan During the Baking of an Oat-Based Bread

Oat and oat products containing β-glucans are associated with many health claims. Both the level and molecular weight of β-glucans play an important role in determining the physiological efficacy of β-glucan in terms of health benefits, including reducing blood cholesterol levels. The objective of this study was to develop a probabilistic model to investigate the effect of various process stages in bread making on the level of β-glucan (BG) and its molecular weight (Mw) distribution using Monte Carlo simulation techniques. Various composite flours were formulated by substituting wheat flour (WF) with oat whole flour (OWF), oat refined flour (ORF), oat bran (OB) or rolled oats (RO). The baseline model predicted an overall mean reduction of 49% in BG in baked bread. The mean Mw of β-glucan in all composite flours was reduced following processing and baking from 1.22 to 0.77 × 106 (g/mol) for OWF + WF, 1.07 to 0.68 × 106 (g/mol) for ORF + WF, 1.17 to 0.75 × 106 (g/mol) for OB + WF and 1.25 to 0.80 × 106 (g/mol) for RO + WF. In all formulated breads, high molecular weight β-glucan was observed to be more susceptible to degradation compared with medium molecular weight and to lower molecular weight. A sensitivity analysis highlighted the negative influence of WF on β-glucan content and the BG reduction with fermentation time. The scenario analysis showed a positive influence on the level of BG with increase addition of oat flour in all formulated breads. The model was validated with experimental data and values were found to be within the confidence interval of predicted BG levels. This model facilitates the optimisation of various steps in the bread making process and highlights the potential for oat flour to improve the nutritional quality of baked bread.

Efeito dos ácidos graxos n-3 e n-6 na expressão de genes do metabolismo de lipídeos e risco de aterosclerose

A aterosclerose, principal responsável pela patogênese do infarto miocárdico e cerebral, bem como pela gangrena e por outras doenças vasculares periféricas, permanece como principal causa de morbidade e mortalidade nas populações "ocidentalizadas". Estima-se que 17,5 milhões de pessoas morreram por doenças cardiovasculares em 2005, o que representou 30% das causas de morte nesse ano, e que, em 2015, 20 milhões de pessoas morrerão por doenças cardiovasculares no mundo. Os ácidos graxos n-3, principalmente os de cadeia longa, encontrados nos peixes, têm-se mostrado particularmente úteis na prevenção e tratamento de doenças como dislipidemias, diabetes mellitus e obesidade, apresentando importante efeito cardioprotetor. Nesse contexto, pesquisas têm evidenciado que ao menos parte dos benefícios dos ácidos graxos eicosapentaenóico e docosahexaenóico sobre o risco de doenças cardiovasculares é decorrente da modulação de genes responsivos aos receptores ativados por proliferadores de peroxissomos e envolvidos no metabolismo lipídico. Nesta revisão, pretende-se expor alguns mecanismos de ação dos ácidos graxos n-3 e n-6 sobre o metabolismo de lipídeos e de lipoproteínas. Conclui-se que muitos aspectos que contribuem para o risco de doenças cardiovasculares são afetados pela ingestão de n-3. Além da redução de triglicérides, fatores como o aumento de adiponectina, a redução da concentração de colesterol plasmático e a melhora do transporte reverso de colesterol também são responsáveis pela redução do risco de aterosclerose promovida pelos ácidos graxos n-3. No entanto, ainda são necessários estudos adicionais para definir mais claramente os mecanismos celulares e moleculares responsáveis pelo efeito cardioprotetor dos ácidos graxos n-3.

An Evaluation of Diazacon as a Potential Contraceptive in Non‐Native Rose‐Ringed Parakeets

ABSTRACT Rose‐ringed parakeets (Psittacula krameri) have become widely established outside their native range through accidental or deliberate release. Potential economic impacts on agriculture, conservation concerns, and mixed public opinion regarding the species have highlighted the need to develop effective but humane management options. Fertility control might provide such a solution if a safe and environmentally benign contraceptive was available. The chemical 20,25‐diazacholesterol dihydrochloride (diazacon) has previously been used to reduce reproductive output in avian species through reduction of blood cholesterol and cholesterol‐dependent reproductive hormones. We orally dosed captive rose‐ringed parakeets with a solution of either 9 mg/kg or 18 mg/kg of diazacon for up to 10 days and found that a dose of 18 mg/kg for 10 days temporarily reduced blood cholesterol levels with no adverse side effects. We evaluated this dose level in a captive population in semi‐natural conditions during the 2008 breeding season and found a significant decrease in fertility. We concluded that diazacon has potential for fertility control in this species if a suitable formulation and delivery system is developed for free‐living populations.

Session 4: CVD, diabetes and cancer A dietary portfolio for management and prevention of heart disease

CHD is the leading cause of worldwide mortality. The prevalence of heart disease has been linked to the adoption of a sedentary lifestyle and the increased dietary dependence on saturated fats from animal sources and the intake of refined foods. Elevated blood cholesterol level is one of the major risk factors for CHD. While cholesterol-lowering drug therapy (statins) has been effective in reducing the risk of heart disease, there are those individuals who are unwilling or because of muscle pains or raised levels of liver or muscle enzymes are unable to take cholesterol-lowering medication. Fortunately, there is evidence linking a number of dietary components to CHD risk reduction. The strength of this evidence has prompted various regulatory bodies to advocate diet as the first line of defence for primary prevention of heart disease. It was therefore decided to combine four dietary components that have been shown to lower blood cholesterol concentrations (nuts, plant sterols, viscous fibre and vegetable protein) in a dietary portfolio in order to determine whether the combined effect is additive. In a metabolically-controlled setting this dietary portfolio has proved to be as effective as a starting dose of a first-generation statin cholesterol-lowering medication in reducing the risk of CHD. The dietary portfolio has also been shown to be effective in sustaining a clinically-significant effect in the long term under a 'real-world' scenario. However, success of the diet depends on compliance and despite the accessibility of the foods adherence has been found to vary greatly. Overall, the evidence supports the beneficial role of the dietary portfolio in reducing blood cholesterol levels and CHD risk.

Effects of Campomanesia xanthocarpa on biochemical, hematological and oxidative stress parameters in hypercholesterolemic patients

Ethnopharmacological relevance In Southern Brazil, the plant Campomanesia xanthocarpa Berg. (Myrtaceae), popularly known as “guavirova” , has been empirically used for its potential effect in reducing blood cholesterol levels. Aim of the study Since there are no scientific data confirming its popular use, the aim of the present study was to investigate the effect of Campomanesia xanthocarpa on biochemical, hematological, anthropometrical and oxidative stress parameters in hypercholesterolemic patients. Materials and methods Thirty three patients were selected according to total cholesterol (TC) levels: 200–240 mg/dL, undesirable level (UL), and >240 mg/dL, hypercholesterolemic level (HL). UL or HL patients were randomly divided into control group (CG), which received placebo capsules, and experimental group 250 (EG 250) or 500 (EG 500), which received either 250 or 500 mg of encapsulated Campomanesia xanthocarpa. All groups received a cholesterol restriction diet and capsules once a day. The biochemical (TC, triglycerides, HDL, LDL and VLDL), hematological (hematocrit and hemoglobin), anthropometrical (weight and abdominal circumference) and oxidative stress (protein carbonyl) parameters were measured before, 45 and 90 days after the treatment started. Results There was no alteration on biochemical, hematological, anthropometric or oxidative stress parameters in UL patients of all groups. However, a significant decrease in TC and LDL levels was observed in HL patients from EG 500 group (reduction of 28 ± 3% and 45 ± 4% to levels before treatment) in relation to CG group patients (reduction of 12 ± 2% and 29 ± 4%). Moreover, a significant reduction in oxidative stress was observed in HL patients of EG 250 (51 ± 12%) and EG 500 groups (34 ± 18%) when compared to levels before treatment. A positive correlation between plasma oxidative stress PC and TC levels was observed. Finally, we found that Campomanesia xanthocarpa extract possesses anti-oxidant properties and 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitory activity in vitro. Conclusion Confirming its popular use, the treatment with Campomanesia xanthocarpa encapsulated reduced blood TC and LDL levels in hypercholesterolemic patients.

Re-evaluating the Rose approach: comparative benefits of the population and high-risk preventive strategies

Options for the prevention of cardiovascular disease, the greatest global cause of death, include population preventive measures (the Rose approach), or specifically seeking out and managing high-risk cases. However, the likely benefit of a population approach has been recently questioned. To compare the estimated effects of population strategies at varying levels of population-wide risk factor reduction and high-risk strategies at varying rates of screening uptake on cardiovascular disease mortality. Data (of 109 954 participants) were pooled from six European general population cohort studies [the high-risk cohorts from the SCORE (Systematic COronary Risk Evaluation) dataset]. The effects of various population and high-risk strategies for the reduction of risk factors were estimated by calculating the change in 10-year risk of cardiovascular disease mortality (SCORE risk) before and after the particular intervention. Risk factors studied were: total cholesterol, blood pressure and smoking. At population level, if a 10-year reduction of blood cholesterol level of 10%, a BP reduction of 10% and a 10% reduction in the prevalence of smoking is considered possible, then 9125 lives per million of the population would be saved over 10 years. In contrast, an approach that treats all high-risk individuals with a polypill containing statin, three half-dose antihypertensives and aspirin, with a 20-80% uptake, would save 1861-7452 lives per million. However, the high-risk estimates are very optimistic, as their achievement would require complete compliance. High-risk and population strategies are complementary. These estimates of the benefits of each may be useful to health planners, when combined with their local knowledge. Recently, benefits of population strategies have been underestimated.

Phytosterol-enriched foods: Role in lowering serum cholesterol level, community authorising and conditions of marketing

Phytosterols are isoprene compounds that may be found in a great variety of different food products. Most important phytosterol compounds are β-sitosterol, campesterol and stigmasterol. Plant sources of phytosterols are oily seeds, nuts, plant oils, grains, and pulses. Many controlled clinical studies have demonstrated their ability to reduce blood cholesterol levels in hyper- and normocholesterolaemic subjects. Investigators report that phytosterol intakes of 2 to 3 g/day reduce low-density lipoprotein (LDL) cholesterol levels by about 7 to 11% in human subjects, while LDL and TG levels show no change. Phytosterol intake higher than 3 g daily results in no greater decrease of LDL level, but even the consumption of 8.6 g/day has no detrimental effect on human health. Documented side effect of elevated phytosterol intake is the reduced level of certain carotenoids in sera but this effect can be balanced by increased consumption of fruits and vegetables rich in carotenoids. Subjects having hereditary sitosterolaemia are highly advised to refrain from consuming foods supplemented with phytosterols. As dietary intake of phytosterols is too low to achieve a significant reduction of cholesterol level, based on the Community legislation of 258/97/EC regulation related to novel foods and novel food ingredients the European Union authorized to use phytosterols in certain food products at a concentration which resulted in a daily phytosterol intake less than 3 g. European survey of European Food Safety Authority (EFSA) shows that only 10 to 15% of the population consume foods supplemented with phytosterols, and phytosterol intake is less than the effective dose. Based on this survey it is supposed that the risk of phytosterol overdose is low. EFSA also stated that — based on the relevant scientific information — regular intake of foods supplemented with phytosterols/phytostanols is in significant correlation with reduced serum cholesterol level. Based on this statement authorized foods enriched with phytosterols will be the first food group legally having health claim for reduced risk of disease since the new Community legislation on nutritional and health claim on foods 1924/2006/EC exists. Consumers will have a scientifically substantiated health claim on the label of these foods: “Plant sterols/stanols have been shown to lower/reduce blood cholesterol. Blood cholesterol lowering may reduce the risk of coronary heart disease”.

Foods fortified with phytosterins: their role in decreasing the cholesterol level in serum, their Community authorization and requirements for placing them to the market

Phytosterols are isoprene compounds that may be found in a great variety of different food products. The most important phytosterol compounds are β-sitosterol, campesterol and stigmasterol. Plant sources of phytosterols are oily seeds, nuts, plant oils, grains, and pulses. Many controlled clinical studies have demonstrated their ability to reduce blood cholesterol levels in hyper- and normocholesterolaemic subjects. Investigators report that phytosterol intakes of 2 to 3 g/d reduce low-density lipoprotein (LDL) cholesterol levels by about 7–11% in human subjects, while LDL and TG levels do not change. Phytosterol intake higher than 3 g daily does not result in higher decrease of LDL level, but about consumption of 8.6 g per day does not have any detrimental effect on human health. A documented side effect of elevated phytosterol intake is the reduced level of certain carotenoids in sera but this effect can be balanced by increased consumption of fruits and vegetables rich in carotenoids. Subjects having hereditary sitosterolemia are highly advised to refrain from consuming foods supplemented with phytosterols. While dietary intake of phytosterols is too low to achieve significant reduce of cholesterol level, based on the Community legislation of 258/97/EC regulation related to novel foods and novel food ingredients, the European Union authorized to use phytosterols in certain food products at a concentration which resulted in a daily phytosterol intake less than 3 g. A European survey of the European Food Safety Authority (EFSA) shows that only 10-15% of the population consume foods supplemented with phytosterols, and phytosterol intake is less than the effective dose. Based on this survey it is supposed that the risk of phytosterols overdose is low. EFSA also stated that – based on the relevant scientific information – regular intake of foods supplemented with phytosterols/phytostanols is in significant correlation with reduced serum cholesterol level. Based on this statement, authorized foods supplemented with phytosterols will be the first food group legally having health claim for reduced risk of disease since the new Community legislation on nutritional and health claim on foods 1924/2006/EC exists. Consumers will have a scientifically substantiated health claim on the label of these foods: “Plant sterols/stanols have been shown to lower/reduce blood cholesterol. Blood cholesterol lowering may reduce the risk of coronary heart disease.”

Functional expression of human HMG-CoA reductase inSaccharomyces cerevisiae: a system to analyse normal and mutated versions of the enzyme in the context of statin treatment

Statins - inhibitors of the 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase - are known to reduce blood cholesterol levels. In this paper, we present a Saccharomyces cerevisiae expression system, which enables quick evaluation of the sensitivity of the wild-type and/or mutant forms of human HMG-CoA reductase towards statins or other drugs. We analysed the sequence of the HMG-CoA reductase gene in DNA extracted from blood samples of 16 patients with cardiovascular disorders. We applied the yeast system to examine the sensitivity of the wild-type and mutated versions of the hHMG-CoA reductase to different types of statins. The yeast and mammalian HMG-CoA reductases demonstrate structural and functional conservation, and expression of human HMG-CoA reductase in yeast complements the lethal phenotype of strains lacking the HMG1 and HMG2 genes. These data indicate that a yeast expression system can serve to study the influence of selected mutations in human HMG-CoA reductase on the sensitivity of the enzyme to commonly prescribed statins. Our results suggest that this model system is suitable for the development and selection of lipid-lowering drugs as well as for the examination of DNA sequence variations in the context of statin therapy.

Efficacy and Safety of Chinese Black Tea (Pu-Ehr) Extract in Healthy and Hypercholesterolemic Subjects

Background/Aims: Water-extracted Chinese black tea (Pu-Ehr) exerts a precipitating effect on mixed bile salt micelles in foods. The amount of black tea extract (BTE) effective for hypercholesterolemia (HC) was examined in humans. Materials and Methods: Animals (test 1) and humans (tests 2–5) were given BTE in the following studies: (test 1) an acute 2-week toxicity test conducted in mice with 2,000 mg/kg BTE or saline; (test 2) a dose-finding 8-week toxicity study with excessive BTE ingestion (0.75 or 1 g/day) in 10 healthy and 10 borderline HC subjects; (test 3) a 1-day acute toxicity test using a (10 g) single-bolus study (n = 10); (test 4) a 5-week long-term safety test (5 g/day, n = 11), and (test 5) a 4-month noncomparative study in 21 HC patients ingesting 1 g/day. Results: The safety study showed no changes in hematological or relevant biochemical parameters in both mice and humans in the acute and long-term toxicity tests. In test 5, significant reductions in total and low-density lipoprotein cholesterol levels accompanied by significant decreases in body weight were observed without affecting other biochemical parameters. Conclusions: BTE significantly reduced blood cholesterol levels in humans and may prove safe and useful in preventing and improving metabolic syndrome-induced arteriosclerosis and/or obesity.

Effects of noni fruit extract on intestinal contractility in rats

Noni (Morinda citrifolia, Rubiaceae) fruits have been wildly used for health benefits. They have been found effective in reducing blood cholesterol levels [1] and may be effective against breast cancer [2] and have antioxidant properties [3]. However, the effects of noni fruit extract on intestinal contractility have never been investigated. The aims of the study were to investigate the effects of noni fruit extract on intestinal contractility in male rats. We particularly examined the effects of the extract on contractions arising spontaneously and by acetylcholine stimulation and investigated the underlying mechanisms. Noni fruits were collected from local gardens and extracted using methanol. The extract was then analyzed by GC/MS. Rats were killed by asphyxiation with CO2 and longitudinal duodenal smooth muscles isolated. Isometric force was measured and the effects of the extract studied. Several agents, previously reported to decrease contraction in other smooth muscles, were found in noni fruit extract. When the extract was applied to spontaneously duodenal contractions, it significantly decreased the contractions. Its effect was dose dependent. The half maximal effect of the extract was observed at the dose of 50mg/100ml (20–100mg/100ml). An elevation of extracellular Ca2+ concentration could not reverse the inhibitory effects of the extract. The extract (100mg/100ml) also inhibited the phasic, but not tonic components of acetylcholine-induced contractions. In conclusion, noni fruit extract has inhibitory effects on intestinal contractility. These may involve contractile machinery that regulates phasic components of contraction.

Antihypercholesterolemic effect of Chinese black tea extract in human subjects with borderline hypercholesterolemia

A water-soluble extract of a traditional Chinese black tea (Pu-Ehr) has been shown to precipitate mixed bile salt micelles in foods. In addition, long-term ingestion of this black tea extract (BTE) significantly reduces blood cholesterol levels in rats. We investigated the effects of BTE tablets (a formula designed to enhance compliance) as a dietary supplement in a 3-month double-blind randomized group comparison study in borderline hypercholesterolemic human subjects (n = 47). All subjects ingested BTE tablets (333 mg) or placebo 3 times daily before meals for 3 months. In the BTE-treated group, the initial mean blood total (6.14 +/- 0.14 mol/L) and low-density lipoprotein (LDL) cholesterol (4.32 +/- 0.14 mol/L) levels decreased with time and were significantly (P < .01) lower (total cholesterol, 5.62 +/- 0.11; LDL cholesterol, 3.81 +/- 0.13 mol/L) after 3 months of ingestion. Furthermore, the mean body weights (P < .05) and triacylglycerol levels (P < .01) were also significantly reduced after 3 months of BTE intake compared with the baseline levels. Significant improvements in the mean LDL cholesterol, body weight, and triacylglycerol values were not accompanied with undesirable changes in other biochemical parameters measured in the subjects. None of the subjects complained of any adverse effects (eg, abdominal distension). The results indicate that BTE intake elicited a significant antihypercholesterolemic effect and might be useful for improving blood cholesterol levels in subjects at risk for heart disease or obesity.