Cholesterol-lowering nutraceuticals and functional foods

Preparation, separation and identification of novel hypocholesterolemic peptides from wheat germ: An in vitro and in silico study

The aim of this study was to prepare, isolate, and identify hypocholesterolemic peptides from wheat germ protein and explore their efficacy. Wheat germ protein was hydrolyzed using four commercial enzymes. Hydrolysate, with the highest in vitro hypocholesterolemic activity was isolated using ultrafiltration and macroporous resin. The fractions with highest binding affinity to sodium taurocholate were evaluated for cholesterol-lowering activity and resistance to digestion using Caco-2 monolayers. Fraction III had the highest cholesterol-lowering activity, reducing the subcutaneous transport and absorption of cholesterol and resisted digestion. Nano-LC-MS/MS and molecular docking were used to identify cholesterol-lowering peptides from Fraction III. Three cholesterol-lowering peptides, FAAGAPP, GAGDIPGGIG, and GPVPDTGIFS, were identified. These peptides exhibited cholesterol micelle solubility, specifically by 76.2 %, 68.3 %, and 64.7 %, respectively. In summary, wheat germ peptides exhibited significant cholesterol-lowering activity in vitro, suggesting their potential for application in functional foods.

Management of blood lipids in post-kidney transplant patients: a systematic review and network meta-analysis

Introduction

The primary objective of this systematic review was to provide an overview of the efficacy and safety of various lipid-lowering therapies in patients post-kidney transplant (PKT), given the limited existing literature. Considering the restricted number of available studies, this work aimed to summarize the existing evidence regarding the effectiveness of different lipid-lowering treatments in PKT patients. The effects of various lipid-lowering therapeutic regimens on lipid levels were compared, and their safety was assessed, with the heterogeneity of treatment protocols acknowledged.

Material and Methods

Randomized controlled trials investigating different treatment regimens (DTRs) for regulating lipid levels in PKT patients were systematically retrieved from PubMed, Cochrane Library, and Embase, from inception to March 2024. Literature quality was assessed employing the Cochrane risk of bias assessment tool. Data analysis and graphical representation were performed employing RevMan5.3 and Stata 20.0. The surface under the cumulative ranking area (SUCRA) compared the effects of DTRs on lipid profiles, incidence of adverse events, and all-cause mortality in PKT patients.

Results

Fifteen studies were included, comprising 5,768 PKT patients and involving 9 treatment regimens. The results revealed that, for changes in high-density lipoprotein cholesterol (HDL-C), the SUCRA rankings from highest to lowest among PKT patients receiving DTRs were statins + ezetimibe (70%), placebo (61.5%), fibrates (57.2%), statins (44.1%), and fish oil (17.3%). Regarding changes in low-DL-C (LDL-C), the SUCRA rankings from highest to lowest among PKT patients receiving DTRs were statins (68.2%), statins + ezetimibe (67.5%), fish oil (53.4%), fibrates (34.5%), and placebo (26.5%). For the change in total cholesterol (TC) levels, a network meta-analysis (NMA) revealed that among PKT patients receiving DTRs, the SUCRA rankings from highest to lowest for TC change were statins + ezetimibe (97.6%), proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9 inhibitors) (74.3%), fish oil (64.3%), statins (61.6%), fibrates (47.2%), placebo (31.6%), calcineurin phosphatase inhibitors (11.9%), and immunosuppressants (11.4%). Regarding the change in triglyceride (TG) levels, a NMA showed that among PKT patients receiving DTRs, the SUCRA rankings from highest to lowest for TG change were fibrates (99.9%), statins (68.9%), PCSK9 inhibitors (66.6%), statins + ezetimibe (55.1%), placebo (49.2%), fish oil (45.0%), immunosuppressants (7.8%), and calcineurin phosphatase inhibitors (7.6%). For the occurrence of kidney transplant failure, a NMA revealed that among PKT patients receiving DTRs, the SUCRA rankings from highest to lowest for reducing the incidence of kidney transplant failure were PCSK9 inhibitors (69.0%), calcineurin phosphatase inhibitors (63.0%), statins (61.5%), placebo (55.1%), steroids (51.8%), immunosuppressants (27.1%), and fibrates (22.5%). Regarding all-cause mortality, a NMA showed that among PKT patients receiving DTRs, the SUCRA rankings from highest to lowest for reducing all-cause mortality were PCSK9 inhibitors (90.5%), statins (55.8%), and placebo (3.7%).

Conclusion

In reducing lipid levels in PKT patients, combination therapy with statins and ezetimibe demonstrated notable advantages and higher effectiveness. PCSK9 inhibitors exhibited greater advantages in reducing adverse events and mortality rates in PKT patients, with higher safety.

Natural phytochemicals as small-molecule proprotein convertase subtilisin/kexin type 9 inhibitors

A decrease in the levels of low-density lipoprotein receptors (LDLRs) leads to the accumulation of LDL cholesterol (LDL-C) in the bloodstream, resulting in hypercholesterolemia and atherosclerotic cardiovascular diseases. Increasing the expression level or inducing the activity of LDLR in hepatocytes can effectively control hypercholesterolemia. Proprotein convertase subtilisin/kexin type 9 (PCSK9) protein, primarily produced in the liver, promotes the degradation of LDLR. Inhibiting the expression and/or function of PCSK9 can increase the levels of LDLR on the surface of hepatocytes and promote LDL-C clearance from the plasma. Thus, targeting PCSK9 represents a new strategy for developing preventive and therapeutic interventions for hypercholesterolemia. Currently, monoclonal antibodies are used as PCSK9 inhibitors in clinical practice. However, the need for oral and affordable anti-PCSK9 medications limits the perspective of choosing PCSK9 inhibitors for clinical usage. Emerging research reports have demonstrated that natural phytochemicals have efficacy in maintaining cholesterol stability and regulating lipid metabolism. Developing novel natural phytochemical PCSK9 inhibitors can serve as a starting point for developing small-molecule drugs to reduce plasma LDL-C levels in patients. In this review, we summarize the current literature on the critical role of PCSK9 in controlling LDLR degradation and hypercholesterolemia, and we discuss the results of studies attempting to develop PCSK9 inhibitors, with an emphasis on the inhibitory effects of natural phytochemicals on PCSK9. Furthermore, we provide insight into the mechanisms of action by which the reported phytochemicals exert their potential PCSK9 inhibitory effects against hypercholesterolemia.

Efficacy Assessment of Five Policosanol Brands and Damage to Vital Organs in Hyperlipidemic Zebrafish by Six-Week Supplementation: Highlighting the Toxicity of Red Yeast Rice and Safety of Cuban Policosanol (Raydel®)

Policosanol is a mixture of long-chain aliphatic alcohols (LCAAs) derived from various plant and insect origins that are marketed by various companies with distinct formulations and brand names. Policosanols offer several beneficial effects to treat dyslipidemia and hypertension; however, a comprehensive functionality comparison of various policosanol brands has yet to be thoroughly explored. In the present study five distinct policosanol brands from different origins and countries, Raydel-policosanol, Australia (PCO1), Solgar-policosanol, USA (PCO2), NutrioneLife-monacosanol, South Korea (PCO3), Mothernest-policosanol, Australia (PCO4), and Peter & John-policosanol, New Zealand (PCO5) were compared via dietary supplementation (1% in diet, final wt/wt) to zebrafish for six weeks to investigate their impact on survivability, blood lipid profile, and functionality of vital organs under the influence of a high-cholesterol diet (HCD, final 4%, wt/wt). The results revealed that policosanol brands (PCO1-PCO5) had a substantial preventive effect against HCD-induced zebrafish body weight elevation and hyperlipidemia by alleviating total cholesterol (TC) and triglycerides (TG) in blood. Other than PCO3, all the brands significantly reduced the HCD's elevated low-density lipoprotein cholesterol (LDL-C). On the contrary, only PCO1 displayed a significant elevation in high-density lipoprotein cholesterol (HDL-C) level against the consumption of HCD. The divergent effect of PCO1-PCO5 against HCD-induced hepatic damage biomarkers, aspartate aminotransferase (AST) and alanine aminotransferase (ALT), was observed. PCO1, PCO2, and PCO4 efficiently curtailed the AST and ALT levels; however, PCO3 and PCO5 potentially aggravated the HCD's elevated plasma AST and ALT levels. Consistently, the hepatic histology outcome revealed the least effectiveness of PCO3 and PCO5 against HCD-induced liver damage. On the contrary, PCO1 exhibited a substantial hepatoprotective role by curtailing HCD-induced fatty liver changes, cellular senescent, reactive oxygen species (ROS), and interleukin-6 (IL-6) production. Likewise, the histological outcome from the kidney, testis, and ovary revealed the significant curative effect of PCO1 against the HCD-induced adverse effects. PCO2-PCO5 showed diverse and unequal results, with the least effective being PCO3, followed by PCO5 towards HCD-induced kidney, testis, and ovary damage. The multivariate interpretation based on principal component analysis (PCA) and hierarchical cluster analysis (HCA) validated the superiority of PCO1 over other policosanol brands against the clinical manifestation associated with HCD. Conclusively, different brands displayed distinct impacts against HCD-induced adverse effects, signifying the importance of policosanol formulation and the presence of aliphatic alcohols on the functionality of policosanol products.

Influence of Lactobacillus rhamnosus Supplementation on the Glycaemic Index, Lipid Profile, and Microbiome of Healthy Elderly Subjects: A Preliminary Randomized Clinical Trial

Aging is a time-dependent complex biological process of organisms with gradual deterioration of the anatomical and physiological functions. The role of gut microbiota is inevitable in the aging process. Probiotic interventions improve gut homeostasis and support healthy aging by enhancing beneficial species and microbial biodiversity in older adults. The present preliminary clinical trial delves into the impact of an 8-week Lactobacillus rhamnosus intervention (10 × 109 CFU per day) on the glycaemic index, lipid profile, and microbiome of elderly subjects. Body weight, body fat, fasting blood glucose, total cholesterol, triglyceride, high-density lipoprotein, and low-density lipoprotein (LDL) are assessed at baseline (Week 0) and after treatment (Week 8) in placebo and probiotic groups. Gaussian regression analysis highlights a significant improvement in LDL cholesterol in the probiotic group (p = 0.045). Microbiome analysis reveals numeric changes in taxonomic abundance at various levels. At the phylum level, Proteobacteria increases its relative frequency (RF) from 14.79 ± 5.58 at baseline to 23.46 ± 8.02 at 8 weeks, though statistically insignificant (p = 0.100). Compared to the placebo group, probiotic supplementations significantly increased the proteobacteria abundance. Genus-level analysis indicates changes in the abundance of several microbes, including Escherichia-Shigella, Akkermansia, and Bacteroides, but only Butyricimonas showed a statistically significant level of reduction in its abundance. Probiotic supplementations significantly altered the Escherichia-Shigella and Sutterella abundance compared to the placebo group. At the species level, Bacteroides vulgatus substantially increases after probiotic treatment (p = 0.021). Alpha and beta diversity assessments depict subtle shifts in microbial composition. The study has limitations, including a small sample size, short study duration, single-strain probiotic use, and lack of long-term follow-up. Despite these constraints, the study provides valuable preliminary insights into the multifaceted impact of L. rhamnosus on elderly subjects. Further detailed studies are required to define the beneficial effect of L. rhamnosus on the health status of elderly subjects.

Exploring Phytochemical Mechanisms in the Prevention of Cholesterol Dysregulation: A Review

Although cholesterol plays a key role in many physiological processes, its dysregulation can lead to several metabolic diseases. Statins are a group of drugs widely used to lower cholesterol levels and cardiovascular risk but may lead to several side effects in some patients. Therefore, the development of a plant-based therapeutic adjuvant with cholesterol-lowering activity is desirable. The maintenance of cholesterol homeostasis encompasses multiple steps, including biosynthesis and metabolism, uptake and transport, and bile acid metabolism; issues arising in any of these processes could contribute to the etiology of cholesterol-related diseases. An increasing body of evidence strongly indicates the benefits of phytochemicals for cholesterol regulation; traditional Chinese medicines prove beneficial in some disease models, although more scientific investigations are needed to confirm their effectiveness. One of the main functions of cholesterol is bile acid biosynthesis, where most bile acids are recycled back to the liver. The composition of bile acid is partly modulated by gut microbes and could be harmful to the liver. In this regard, the reshaping effect of phytochemicals on gut microbiota has been widely reported in the literature for its significance. Therefore, we reviewed studies conducted over the past 5 years elucidating the regulatory effects of phytochemicals or herbal medicines on cholesterol metabolism. In addition, their effects on the recomposition of gut microbiota and bile acid metabolism due to modulation are discussed. This review aims to provide novel insights into the treatment of cholesterol dysregulation and the anticipated development of natural-based compounds in the near and far future.

Novel Synthesis of Phytosterol Ferulate Using Acidic Ionic Liquids as a Catalyst and Its Hypolipidemic Activity

Phytosterol ferulate (PF) is quantitively low in rice, corn, wheat, oats, barley, and millet, but it is potentially effective in reducing plasma lipids. In this study, PF was synthesized for the first time using acidic ionic liquids as a catalyst. The product was purified, characterized using Fourier transform infrared, mass spectroscopy, and nuclear magnetic resonance, and ultimately confirmed as the desired PF compound. The conversion of phytosterol surpassed an impressive 99% within just 2 h, with a selectivity for PF exceeding 83%. Plasma lipid-lowering activity of PF was further investigated by using C57BL/6J mice fed a high-fat diet as a model. Supplementation of 0.5% PF into diet resulted in significant reductions in plasma total cholesterol, triacylglycerols, and nonhigh-density lipoprotein cholesterol by 13.7, 16.9, and 46.3%, respectively. This was accompanied by 55.8 and 36.3% reductions in hepatic cholesterol and total lipids, respectively, and a 22.9% increase in fecal cholesterol excretion. Interestingly, PF demonstrated a higher lipid-lowering activity than that of its substrates, a physical mixture of phytosterols and ferulic acid. In conclusion, an efficient synthesis of PF was achieved for the first time, and PF had the great potential to be developed as a lipid-lowering dietary supplement.

Mangiferin alleviates trimethylamine-N-oxide (TMAO)-induced atherogenesis and modulates gut microbiota in mice

Trimethylamine-N-oxide (TMAO), originating from dietary trimethylamine-containing nutrients such as choline, has been recognized as a risk factor for atherosclerosis. Mangiferin is a bioactive xanthone initially extracted from mango (Mangifera indica). The present study aimed to investigate the effect of mangiferin on TMAO-induced atherogenesis in mice fed a high-choline diet. Female ApoE-/- mice were randomly divided into three groups and fed either a control diet, a high-choline diet with 1% free choline, or an experimental diet with 1% free choline plus 0.5% mangiferin for 15 weeks. Our results showed that a high-choline diet elevated plasma TMAO levels, accelerated atherogenesis, promoted cholesterol accumulation, and reduced the generation of short-chain fatty acids (SCFAs) by gut microbes. Mangiferin alleviated inflammation, and lowered plasma total cholesterol levels by facilitating the elimination of neutral and acidic sterols in feces, resulting in a 16.7-29.0% reduction in aortic atherosclerotic lesions. Notably, mangiferin could favorably remodel the composition of the gut microbiota by fostering the growth of the beneficial taxa Akkermansia, Parabacteroides, and Bifidobacteriaceae, while reducing the relative abundance of the pathogenic genus Helicobacter. This modulation led to a decrease in plasma lipopolysaccharide levels, enhanced the production of total SCFAs by gut microbes, and reduced susceptibility to atherosclerosis. In conclusion, mangiferin exhibited its ability to alleviate TMAO-induced atherosclerosis through its anti-inflammatory, cholesterol-lowering, and gut microbial modulatory activities.

Brazilian green propolis extracts modulate cholesterol homeostasis in a preclinical guinea pig model: an in vitro and in vivo study

Green propolis produced by Apis melífera bees, having Baccharis dracunculifolia D.C. (Asteraceae) as the primary botanical source, has been used in traditional medicine to treat numerous disorders. However, studies evaluating propolis' potential in treating cardiovascular diseases via its effects on cholesterol metabolism are lacking. Therefore, this study investigated the effects of green propolis extracts on lipid metabolism in hypercholesterolemic guinea pigs. Chemical characterization of ethanolic extracts of green propolis samples was undertaken using HPLC. The in vitro characterization included an evaluation of the antioxidant capacity of the hydroalcoholic extract of green propolis (DPPH and FRAP assays) and its ability to act as an inhibitor of the HMG-CoA reductase enzyme. In vivo, we investigated the effect of the hydroalcoholic extract of green propolis on lipid metabolism in hypercholesterolemic guinea pigs. Results obtained validated previous reports of significant antioxidant activity. HPLC analysis confirmed that coumaric acid, artepillin C, and baccharin were the most common and abundant compounds in green propolis samples among the studied compounds. Furthermore, the compounds in these extracts acted as effective HMG-CoA reductase inhibitors in vitro. In vivo assays demonstrated that a hypercholesterolemic diet significantly reduced serum levels of the HDL cholesterol fraction. Simvastatin and propolis hydroalcoholic extracts promoted a significant increase in HDL cholesterol, suggesting that these extracts can improve the serum lipid profile of hypercholesterolemic guinea pigs. Results obtained in this study provide a perspective on the possible hypocholesterolemic effect of green propolis, suggesting that it can improve the serum lipid profile in hypercholesterolemic guinea pigs.

Effect of 4-Week Consumption of Soy Kori-tofu on Cardiometabolic Health Markers: A Double-Blind Randomized Controlled Cross-Over Trial in Adults with Mildly Elevated Cholesterol Levels

Kori-tofu is a frozen soy tofu, and soy consumption is associated with positive effects on cardiometabolic health markers. We aimed to assess the potential of Kori-tofu to improve cardiometabolic health outcomes in humans by repetitive daily consumption. In a double-blind randomized controlled cross-over trial, 45 subjects aged 40-70 years with (mildly) elevated cholesterol levels, received a four week Kori-tofu intervention or whey protein control intervention with a four week wash-out period in between. Cardiometabolic biomarkers were measured before and after both interventions. A significant decrease in total, low-density lipids (LDL), and high-density lipids (HDL) cholesterol, Hemoglobin A1c (HbA1c), fructosamine and systolic blood pressure was observed within the Kori-tofu intervention. However, many of these findings were also observed in the control intervention. Only adiponectin changes were different between treatments but did not change significantly within interventions. Improvements in cardiometabolic markers within the Kori-tofu intervention point toward potential beneficial health effects. Due to the lack of significant effects as compared to control, there is, however, currently no substantiating evidence to claim that Kori-tofu has beneficial effects on cardiometabolic health.

L-Arabinose improves hypercholesterolemia via regulating bile acid metabolism in high-fat-high-sucrose diet-fed mice

Background

Hypercholesterolemia is closely associated with an increased risk of cardiovascular diseases. l-Arabinose exhibited hypocholesterolemia properties, but underlying mechanisms have not been sufficiently investigated. This study aimed to elucidate the mechanisms of l-arabinose on hypocholesterolemia involving the enterohepatic circulation of bile acids.

Methods

Thirty six-week-old male mice were randomly divided into three groups: the control group and the high-fat-high-sucrose diet (HFHSD)-fed group were gavaged with distilled water, and the l-arabinose-treated group were fed HFHSD and received 400 mg/kg/day l-arabinose for 12 weeks. Serum and liver biochemical parameters, serum and fecal bile acid, cholesterol and bile acid metabolism-related gene and protein expressions in the liver and small intestine were analyzed.

Results

l-Arabinose supplementation significantly reduced body weight gain, lowered circulating low-density lipoprotein cholesterol (LDL-C) while increasing high-density lipoprotein cholesterol (HDL-C) levels, and efficiently alleviated hepatic inflammation and lipid accumulations in HFHSD-fed mice. l-Arabinose inhibited cholesterol synthesis via downregulation of 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR). Additionally, l-arabinose might facilitate reverse cholesterol transport, evidenced by the increased mRNA expressions of low-density lipoprotein receptor (LDL-R) and scavenger receptor class B type 1 (SR-B1). Furthermore, l-arabinose modulated ileal reabsorption of bile acids mainly through downregulation of ileal bile acid-binding protein (I-BABP) and apical sodium-dependent bile acid transporter (ASBT), resulting in the promotion of hepatic synthesis of bile acids via upregulation of cholesterol-7α-hydroxylase (CYP7A1).

Conclusions

l-Arabinose supplementation exhibits hypocholesterolemic effects in HFHSD-fed mice primarily due to regulation of bile acid metabolism-related pathways.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12986-022-00662-8.

Artichoke and bergamot extracts: a new opportunity for the management of dyslipidemia and related risk factors

The relationship between low LDL-C (cholesterol associated with low-density lipoprotein) and a lower relative risk of developing cardiovascular disease (CVD) has been widely demonstrated. Although from a pharmacological point of view, statins, ezetimibe and PCSK inhibitors, alone or in combination are the front and center of the therapeutic approaches for reducing LDL-C and its CV consequences, in recent years nutraceuticals and functional foods have increasingly been considered as a valid support in the reduction of LDL-C, especially in patients with mild/moderate hyperlipidemia - therefore not requiring pharmacological treatment - or in patients intolerant to statins or other drugs. An approach also shared by the European Atherosclerosis Society (EAS). Of the various active ingredients with hypolipidemic properties, we include the artichoke (Cynara cardunculus, Cynara scolymus) and the bergamot (Citrus bergamia) which, thanks essentially to the significant presence of polyphenols in their extracts, can exert this action associated with a number of other complementary inflammation and oxidation benefits. In light of these evidence, this review aimed to describe the effects of artichoke and bergamot in modifying the lipid and inflammatory parameters described in in vitro, in vivo and clinical studies. The available data support the use of standardized compositions of artichoke and bergamot extracts, alone or in combination, in the treatment of mild to moderate dyslipidemia, in patients suffering from metabolic syndrome, hepatic steatosis, or intolerant to common hypolipidemic treatments.

Production, Characterization, Delivery, and Cholesterol-Lowering Mechanism of Phytosterols: A Review

Phytosterols are natural plant-based bioactive compounds that can lower blood cholesterol levels and help prevent cardiovascular diseases. Consequently, they are being utilized in functional foods, supplements, and pharmaceutical products designed to improve human health. This paper summarizes different approaches to isolate, purify, and characterize phytosterols. It also discusses the hypolipidemic mechanisms of phytosterols and their impact on cholesterol transportation. Phytosterols have a low water-solubility, poor chemical stability, and limited bioavailability, which limits their utilization and efficacy in functional foods. Strategies are therefore being developed to overcome these shortcomings. Colloidal delivery systems, such as emulsions, oleogels, liposomes, and nanoparticles, have been shown to be effective at improving the water-dispersibility, stability, and bioavailability of phytosterols. These delivery systems can be used to incorporate phytosterols into a broader range of cholesterol-lowering functional foods and beverages. We also discuses several issues that need to be addressed before these phytosterol delivery systems can find widespread commercial utilization.

Trends in Nutritional Biomarkers by Demographic Characteristics Across 14 Years Among US Adults

Background: Understanding trend in nutritional status is crucial to inform national health priorities to improve diets and reduce related diseases. The present study aimed to analyze trends in the concentrations of all measured nutritional biomarkers and their status among US adults across 14 years.

Methods: Trends on the concentrations of nutritional biomarkers and nutritional status evaluated by the prevalence of deficiency, inadequacy, excess, and dyslipidemia were analyzed among US adults in 7 cross-sectional National Health and Nutrition Examination Surveys (NHANES 2003–2016) and by age, sex, race/ethnicity, and socioeconomic status.

Results: A total of 38,505 participants (weighted mean age of 47.2 years, 51.4% women) were included in the present study. Across 14 years, increased trends were found in red blood cell (RBC) folate, serum vitamin B₁₂, vitamin D and albumin, the prevalence of iodine deficiency, vitamin B₆ inadequacy, and hypophosphatemia, whereas decreased trends were observed in serum vitamin E, phosphorus, total calcium, total protein, apolipoprotein B (Apo B), low-density-lipoprotein cholesterol (LDL-C), triglyceride (TG), total cholesterol (TC), blood lead, cadmium, mercury, and the prevalence of vitamin C deficiency, vitamin D inadequacy, iodine excess, and dyslipidemia with elevated LDL-C, TC, TG, and lowered HDL/LDL. Non-Hispanic blacks (NHB) and participants with low socioeconomic status were accounted for the poor nutritional status of most biomarkers compared to their comparts.

Conclusion: Most nutritional biomarkers and their status were improved among US adults from 2003 to 2016, but some specific populations should be paid much attention to improve their nutritional status, especially for NHB and participants with low socioeconomic status.

Development of Cholesterol-Lowering and Detox Formulations Using Bentonite and Herbal Ingredients

Detoxification enzymes involved in human metabolism works to minimize the potential xenobiotic-induced damage constantly. Studies have revealed that toxin accumulation plays an important role in the etiology of cardiovascular disease. This study has been designed to provide evidence of medicinal use of bentonite, turmeric (Curcuma longa L.), grape (Vitis vinifera L.) seed, flaxseed (Linum usitatissimum L.), and psyllium (Plantago ovata L.) as detoxification and cholesterol-lowering agents using a hypercholesterolemic model in mice. The potential hypocholesterolemic effects and detoxification ability of these ingredients were evaluated at the same time: Total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglyceride, glucose, aspartate aminotransferase, alanine aminotransferase, malondialdehyde, plasma total antioxidant activity, nitric acid, leptin levels and glutathione, glutathione peroxidase, lipid peroxidation, superoxide dismutase and catalase values were measured. It was determined that GBTF group (grape seed extract, bentonite, turmeric, and flaxseed), GBTP group (grape seed extract, bentonite, turmeric, and psyllium), and GBT group (grape seed extract, bentonite, and turmeric) of the tested materials decreased the serum total cholesterol concentration by 64.8, 57.5, and 48.9%, respectively, in mice fed a high cholesterol diet. In addition, it was determined that some detoxification parameters such as superoxide dismutase, catalase, glutathione, and glutathione peroxidase were statistically significantly reversed in GBTF, GBTP, and GBT groups. Flaxseed, psyllium, and bentonite clay did not show significant effects in reducing total cholesterol; however, GBTF, GBTP, and GBT groups interventions had a significant effect in reducing total cholesterol levels. Moreover, it was observed that adding flaxseed or psyllium to the GBT group increased the cholesterol-lowering effect. Therefore, it can be thought that this significant effect is due to the synergistic effect of the raw materials. When the results obtained were evaluated, it was seen that the cholesterol-lowering and detoxification effects of the combinations were higher than from the effect of natural material used alone. As a result, combinations of some of these ingredients have a positive effect on reducing the risk of cardiovascular disease.

Associations of spicy food flavour and intake frequency with blood lipid levels and risk of abnormal serum lipid levels in Chinese rural population: a cross-sectional study

OBJECTIVE

The purpose of the current study was to investigate associations between spicy food intake and serum lipids levels in Chinese rural population.

DESIGN

Information on spicy food flavour and intake frequency was obtained using a two-item questionnaire survey. Dietary data were collected using a validated thirteen-item FFQ. Fasting blood samples were collected and measured for total cholesterol (TC), TAG, HDL-cholesterol and LDL-cholesterol. Multivariate linear and logistic regression models were employed to examine the relationship between spicy food and serum lipids levels according to the spicy food flavour and intake frequency, respectively.

SETTING

A cross-sectional study in Henan Province.

PARTICIPANTS

38 238 participants aged 18-79 years old.

RESULTS

Spicy flavour and intake frequency were consistently associated with decreased TC and non-HDL-cholesterol levels but mildly associated with elevated TAG levels. Each level increment in spicy flavour was inversely associated with high TC (OR: 0·91; 95 % CI 0·88, 0·93) and high non-HDL-cholesterol (OR: 0·88; 95 % CI 0·85, 0·91) but positively associated with high TAG (OR: 1·04; 95 % CI 1·01, 1·07). Similarly, 1-d increment in spicy food intake frequency was also inversely associated with high TC (OR: 0·92; 95 % CI 0·91, 0·94) and high non-HDL-cholesterol (OR: 0·91; 95 % CI 0·89, 0·93) but positively associated with high TAG (OR: 1·04; 95 % CI 1·02, 1·06).

CONCLUSIONS

Spicy food intake was mildly associated with increased risk of abnormal TAG level, significantly associated with decreased risk of abnormal TC and non-HDL levels. Spicy food intake may be contribute to the management of lipid levels.

Cholesterol-lowering activity of protocatechuic acid is mediated by increasing the excretion of bile acids and modulating gut microbiota and producing short-chain fatty acids

The present study aimed to investigate the effects of protocatechuic acid (PCA) on plasma lipid profiles and associated mechanisms with a focus on reshaping gut microbiota. Twenty-four male hamsters were randomly divided into three groups receiving a high-cholesterol diet (HCD) and two HCD diets containing 0.5% (PL) and 1% (PH) PCA, respectively. Feeding PL and PH diets for six weeks significantly reduced plasma total cholesterol by 18% and 24%, respectively. PL and PH diets also significantly lowered plasma non-HDL cholesterol by 37% and 44%, respectively. This was accompanied by an increase in fecal short-chain fatty acids (SCFAs) and fecal bile acids with up-regulation on gene of cholesterol 7α-hydroxylase and down-regulation of 3-hydroxy-3-methylglutaryl-CoA reductase in the liver. Dietary PCA supplementation decreased hepatic lipid accumulation, whereas it increased fecal excretion of lipids. The 16S rRNA analysis found that dietary PCA significantly reduced the ratio of Firmicutes to Bacteroidetes and increased the relative abundance of Bacteroidales S24-7, whereas it reduced the abundance of Lactobacillaceae. It was concluded that dietary PCA favorably modulated plasma lipid profiles and prevented the accumulation of hepatic cholesterol and lipid disposition. Such effect was mediated at least partially by increasing gut production of SCFAs and fecal excretion of bile acids via modulating the gut microbiome.

Proanthocyanidins and Where to Find Them: A Meta-Analytic Approach to Investigate Their Chemistry, Biosynthesis, Distribution, and Effect on Human Health

Proanthocyanidins (PACs) are a class of polyphenolic compounds that are attracting considerable interest in the nutraceutical field due to their potential health benefits. However, knowledge about the chemistry, biosynthesis, and distribution of PACs is limited. This review summarizes the main chemical characteristics and biosynthetic pathways and the main analytical methods aimed at their identification and quantification in raw plant matrices. Furthermore, meta-analytic approaches were used to identify the main plant sources in which PACs were contained and to investigate their potential effect on human health. In particular, a cluster analysis identified PACs in 35 different plant families and 60 different plant parts normally consumed in the human diet. On the other hand, a literature search, coupled with forest plot analyses, highlighted how PACs can be actively involved in both local and systemic effects. Finally, the potential mechanisms of action through which PACs may impact human health were investigated, focusing on their systemic hypoglycemic and lipid-lowering effects and their local anti-inflammatory actions on the intestinal epithelium. Overall, this review may be considered a complete report in which chemical, biosynthetic, ecological, and pharmacological aspects of PACs are discussed.

The Effect of Probiotics on Health Outcomes in the Elderly: A Systematic Review of Randomized, Placebo-Controlled Studies

Increasing evidence suggests that probiotic supplementation may be efficacious in counteracting age-related shifts in gut microbiota composition and diversity, thereby impacting health outcomes and promoting healthy aging. However, randomized controlled trials (RCTs) with probiotics in healthy older adults have utilized a wide variety of strains and focused on several different outcomes with conflicting results. Therefore, a systematic review was conducted to determine which outcomes have been investigated in randomized controlled trials with probiotic supplementation in healthy older adults and what has been the effect of these interventions. For inclusion, studies reporting on randomized controlled trials with probiotic and synbiotic supplements in healthy older adults (defined as minimum age of 60 years) were considered. Studies reporting clinical trials in specific patient groups or unhealthy participants were excluded. In addition to assessment of eligibility and data extraction, each study was examined for risk of bias and quality assessment was performed by two independent reviewers. Due to the heterogeneity of outcomes, strains, study design, duration, and methodology, we did not perform any meta-analyses and instead provided a narrative overview of the outcomes examined. Of 1997 potentially eligible publications, 17 studies were included in this review. The risk of bias was low, although several studies failed to adequately describe random sequence generation, allocation concealment, and blinding. The overall study quality was high; however, many studies did not include sample calculations, and the majority of studies had a small sample size. The main outcomes examined in the trials included microbiota composition, immune-related measurements, digestive health, general well-being, cognitive function, and lipid and other biomarkers. The most commonly assessed outcome with the most consistent effect was microbiota composition; all but one study with this outcome showed significant effects on gut microbiota composition in healthy older adults. Overall, probiotic supplementation had modest effects on markers of humoral immunity, immune cell population levels and activity, as well as the incidence and duration of the common cold and other infections with some conflicting results. Digestive health, general-well-being, cognitive function, and lipid and other biomarkers were investigated in a very small number of studies; therefore, the impact on these outcomes remains inconclusive. Probiotics appear to be efficacious in modifying gut microbiota composition in healthy older adults and have moderate effects on immune function. However, the effect of probiotic supplementation on other health outcomes remains inconclusive, highlighting the need for more well-designed, sufficiently-powered studies to investigate if and the mechanisms by which probiotics impact healthy aging.

Rutin and Quercetin Decrease Cholesterol in HepG2 Cells but Not Plasma Cholesterol in Hamsters by Oral Administration

Rutin (R) and quercetin (Q) are two widespread dietary flavonoids. Previous studies regarding the plasma cholesterol-lowering activity of R and Q generated inconsistent results. The present study was therefore carried out to investigate the effects of R and Q on cholesterol metabolism in both HepG2 cells and hypercholesterolemia hamsters. Results from HepG2 cell experiments demonstrate that both R and Q decreased cholesterol at doses of 5 and 10 µM. R and Q up-regulated both the mRNA and protein expression of sterol regulatory element binding protein 2 (SREBP2), low-density lipoprotein receptor (LDLR), and liver X receptor alpha (LXRα). The immunofluorescence study revealed that R and Q increased the LDLR expression, while only Q improved LDL-C uptake in HepG2 cells. Results from hypercholesterolemia hamsters fed diets containing R (5.5 g/kg diet) and Q (2.5 g/kg diet) for 8 weeks demonstrate that both R and Q had no effect on plasma total cholesterol. In the liver, only Q reduced cholesterol significantly. The discrepancy between the in vitro and in vivo studies was probably due to a poor bioavailability of flavonoids in the intestine. It was therefore concluded that R and Q were effective in reducing cholesterol in HepG2 cells in vitro, whereas in vivo, the oral administration of the two flavonoids had little effect on plasma cholesterol in hamsters.

Effects of Bilberry and Oat intake on lipids, inflammation and exercise capacity after Acute Myocardial Infarction (BIOAMI): study protocol for a randomized, double-blind, placebo-controlled trial

Background

Bilberries from Sweden, rich in polyphenols, have shown cholesterol-lowering effects in small studies, and the cholesterol-lowering properties of oats, with abundant beta-glucans and potentially bioactive phytochemicals, are well established. Both may provide cardiometabolic benefits following acute myocardial infarction (AMI), but large studies of adequate statistical power and appropriate duration are needed to confirm clinically relevant treatment effects. No previous study has evaluated the potential additive or synergistic effects of bilberry combined with oats on cardiometabolic risk factors. Our primary objective is to assess cardioprotective effects of diet supplementation with dried bilberry or with bioprocessed oat bran, with a secondary explorative objective of assessing their combination, compared with a neutral isocaloric reference supplement, initiated within 5 days following percutaneous coronary intervention (PCI) for AMI.

Methods

The effects of Bilberry and Oat intake on lipids, inflammation and exercise capacity after Acute Myocardial Infarction (BIOAMI) trial is a double-blind, randomized, placebo-controlled clinical trial. A total of 900 patients will be randomized post-PCI to one of four dietary intervention arms. After randomization, subjects will receive beverages with bilberry powder (active), beverages with high-fiber bioprocessed oat bran (active), beverages with bilberry and oats combined (active), or reference beverages containing no active bilberry or active oats, for consumption twice daily during a 3-month intervention. The primary endpoint is the difference in LDL cholesterol change between the intervention groups after 3 months. The major secondary endpoint is exercise capacity at 3 months. Other secondary endpoints include plasma concentrations of biochemical markers of inflammation, metabolomics, and gut microbiota composition after 3 months.

Discussion

Controlling hyperlipidemia and inflammation is critical to preventing new cardiovascular events, but novel pharmacological treatments for these conditions are expensive and associated with negative side effects. If bilberry and/or oat, in addition to standard medical therapy, can lower LDL cholesterol and inflammation more than standard therapy alone, this could be a cost-effective and safe dietary strategy for secondary prevention after AMI.

Trial registration

ClinicalTrials.gov NCT03620266. Registered on August 8, 2018.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-021-05287-5.

Effect of Beetroot Consumption on Serum Lipid Profile: A Systematic Review and Meta-Analysis

Beetroot has recently become very popular among people as a medicinal superfood that decreases blood pressure and improves athletes' performance. The present meta-analysis aimed to investigate the effect of beetroot consumption on serum lipid profile. A literature search was conducted covering PubMed, ISI Web of Science, Scopus, and Google scholar of English human subject randomized clinical trials (RCT) up to December 2020. Pooled results showed that beetroot consumption had no significant effect on any of the variables. The mean difference (95% CI) between intervention and control groups for TC was 1.25 (-0.03, 2.53), for TG -0.47 (-1.16, 0.21), for HDL 0.54 (-0.13, 1.21) and for LDL was -0.48(-1.04, 0.09). Subgroup analysis by the health condition of subjects, the form of beetroot consumption, and type of intervention showed no significant differences. It can be concluded that beetroot cannot be categorized as an effective supplementation for adjustment of lipid profile.

Fatty Acid Profile and Squalene, Tocopherol, Carotenoid, Sterol Content of Seven Selected Consumed Legumes

Legume seeds (Fabaceae) of seven species Cyamopsis tetragonoloba (guar), Glycine max (soybean), Lablab purpureus (lablab-bean), Macrotyloma uniflorum (kulthi bean), Phaseolus vulgaris (common bean), Trigonella foenum-graecum (fenugreek) and Vigna unguiculata (cowpea) were studied. The oil yield ranged from 1.2 to 20.2% dw, in the lablab-bean and soybean, respectively. The polyunsaturated fatty acids (PUFA) constituted the largest part (46-78%) of total fatty acids in studied legumes. γ-Tocopherol was the predominant tocopherol (T) homologue (61-95%) in most of the tested legumes with the exception of fenugreek (α-T, 97%) and cowpea (γ-T and δ-T, nearly equal). The β-sitosterol was the main sterol (51-56%) in most legumes. While in cowpea, lablab-bean and kulthi bean the main sterols were β-sitosterol and Δ5-stigmasterol (28-37% and 14-42%, respectively). Squalene was detected only in kulthi bean and lablab-bean (58 and 284 mg/100 g oil). The total concentration of carotenoids, tocochromanols, and sterols in the studied legumes was 0.2-9.2, 12.4-276.0, and 350-8,542 mg/100 g oil, respectively. Based on the levels of minor lipophilic compounds of this study, C. tetragonoloba, T. foenum-graecum and G. max seem to have a better nutritional value compared to P. vulgaris, V. unguiculata, L. purpureus, and M. uniflorum.

Jaboticaba (Myrciaria cauliflora) Peel Supplementation Prevents Hepatic Steatosis Through Hypolipidemic Effects and Cholesterol Metabolism Modulation in Diet-Induced NAFLD Rat Model

Jaboticaba (Myrciaria cauliflora), a Brazilian fruit, is a good source of dietary fiber and phenolic compounds, which are concentrated mainly in the peel. These compounds have been considered promising in prevention and treatment of hypercholesterolemia and hepatic steatosis. In this study, we investigated the effects of 4% jaboticaba peel powder (JPP) supplementation on cholesterol metabolism and hepatic steatosis in livers of rats fed a high-fat (HF) diet. The rats were fed a standard AIN-93M (control) diet or an HF diet containing 32% lard and 1% cholesterol, both with and without 4% JPP. The M. cauliflora peel composition revealed a low-lipid high-fiber content and phenolic compounds. The phenolic compounds in JPP, tentatively identified by high-performance liquid chromatography and mass spectrometry (HPLC-MS/MS) analysis, were confirmed to contain phenolic acids, flavonoids, and anthocyanins. Moreover, JPP presented significant antioxidant activity in vitro and was not cytotoxic to HepG2 cells, as determined by the lactate dehydrogenase (LDH) assay. After 6 weeks of treatment, our results showed that JPP supplementation increased lipid excretion in feces, reduced serum levels of total cholesterol and nonhigh-density lipoprotein cholesterol, decreased serum aspartate aminotransferase (AST) activity, and attenuated hepatic steatosis severity in rats fed the HF diet. Furthermore, JPP treatment downregulated expression of ACAT-1, LXR-α, CYP7A1, and ABCG5 genes. Therefore, jaboticaba peel may represent a viable dietary strategy to prevent nonalcoholic fatty liver disease as the JPP treatment alleviated hepatic steatosis through improvement of serum lipid profiles and modulation of mRNA expression of genes involved in cholesterol metabolism.

Hawthorn fruit extract reduced trimethylamine-N-oxide (TMAO)-exacerbated atherogenesis in mice via anti-inflammation and anti-oxidation

Background

Trimethylamine-N-oxide (TMAO) is an independent risk factor for atherosclerosis. Consumption of hawthorn fruit is believed to be cardio-protective, yet whether it is able to suppress the TMAO-induced atherosclerosis remains unexplored. The present study was to investigate the effects of hawthorn fruit extract (HFE) on TMAO-exacerbated atherogenesis.

Methods

Five groups of male Apolipoprotein E knock-out (ApoE^−/−) mice were fed a low-fat diet (LFD), a Western high-fat diet (WD), or one of the three WDs containing 0.2% TMAO (WD + TMAO), 0.2% TMAO plus 1% HFE (WD + TMAO + L-HFE), or 0.2% TMAO plus 2% HFE (WD + TMAO + H-HFE), respectively. After 12-weeks of intervention, plasma levels of TMAO, lipid profile, inflammatory biomarkers, and antioxidant enzyme activities were measured. Atherosclerotic lesions in the thoracic aorta and aortic sinus were evaluated. The sterols and fatty acids in the liver and feces were extracted and measured. Hepatic expressions of inflammatory biomarkers and antioxidant enzymes were analyzed.

Results

Dietary TMAO accelerated atherogenesis, exacerbated inflammation, and reduced antioxidant capacities in the plasma and the liver. TMAO promoted hepatic cholesterol accumulation by inhibiting fecal excretion of acidic sterols. HFE could dose-dependently reduce the TMAO-aggravated atherosclerosis and inflammation. HFE was also able to reverse the TMAO-induced reduction in antioxidant capacity by up-regulating the expression of antioxidant enzymes including superoxide dismutase 1 (SOD1), SOD2, glutathione peroxidase 3 (GSH-Px3), and catalase (CAT) in the liver. Moreover, the hepatic cholesterol content was lowered by HFE via enhanced fecal excretion of neutral and acidic sterols.

Conclusions

The present results indicated that HFE was able to reduce the TMAO-exacerbated atherogenesis by attenuating inflammation and improving antioxidant capacity at least in mice.

Graphic abstract

Laser light as a promising approach to improve the nutritional value, antioxidant capacity and anti-inflammatory activity of flavonoid-rich buckwheat sprouts

Buckwheat sprouts are rich in several nutrients such as antioxidant flavonoids that have a positive impact on human health. Although there are several studies reported the positive impact of laser light on crop plants, no studies have applied laser light to enhance the nutritive values of buckwheat sprouts. Herein, the contents of health-promoting minerals, metabolites and enzymes as well as the antioxidant and anti-inflammatory activities were determined in laser-treated (He-Ne laser, 632 nm, 5 mW) common buckwheat (CBW) and tartarybuckwheat (TBW) sprouts. Out of 49 targeted minerals, vitamins, pigments and antioxidants, more than 35 parameters were significantly increased in CBW and/or TBW sprouts by laser light treatment. Also, laser light boosted the antioxidant capacity and anti-inflammatory activities through inhibiting cyclooxygenase-2 and lipoxygenase activities, particularly in TBW sprouts. Accordingly, laser light could be recommended as a promising method to improve the nutritional and health-promoting values of buckwheat sprouts.

Vinegars but not acetic acid are effective in reducing plasma cholesterol in hamsters fed a high-cholesterol diet

The present study compares the effect of two types of vinegars, Balsamic vinegar of Modena (BV) and Chinese Shanxi vinegar (SV), with acetic acid on plasma cholesterol using hamsters as a model. Hamsters (n = 40) were divided into five groups (n = 8 each) with two control groups being fed a low-cholesterol diet (LCD) or a high-cholesterol diet containing 0.2% cholesterol (HCD). The three experimental groups were given a HCD diet and gavaged with 8 ml of BV, SV, and acetic acid solution (AC) per kg body weight, respectively. Acetic acid in BV, SV, and AC solutions was adjusted with water to be 20 mg ml-1. The whole experiment lasted for 9 weeks. Plasma total cholesterol (TC) in BV and SV groups but not in the AC group was reduced by 17% and 20%, respectively, compared with that in HCD hamsters. BV and SV significantly reduced cholesterol in the liver and increased the fecal excretion of neutral sterols and bile acids. Real-time PCR analysis demonstrated that BV and SV significantly up-regulated the mRNA of cholesterol 7 alpha-hydroxylase (CYP7A1) in the liver. In conclusion, BV and SV but not AC were effective in reducing plasma TC and non-HDL-C concentrations at least in hypercholesterolemic hamsters.

Ursolic acid alleviates hypercholesterolemia and modulates the gut microbiota in hamsters

Ursolic acid (UA) is a triterpenoid acid widely abundant in fruits and vegetables such as apple, blueberry and cranberry. The present study was carried out to investigate the effect of UA supplementation in diet on blood cholesterol, intestinal cholesterol absorption and gut microbiota in hypercholesterolemic hamsters. A total of thirty-two hamsters were randomly assigned to four groups and given a non-cholesterol diet (NCD), a high-cholesterol diet containing 0.1% cholesterol (HCD), an HCD diet containing 0.2% UA (UAL), or an HCD diet containing 0.4% UA (UAH) for 6 weeks. Results showed that UA supplementation reduced plasma cholesterol by 15-16% and inhibited intestinal cholesterol absorption by 2.6-9.2%. The in vitro micellar cholesterol solubility experiment clearly demonstrated that UA could displace 40% cholesterol from micelles. In addition, UA decreased the ratio of Firmicutes to Bacteroidetes, whereas it enhanced the growth of short chain fatty acid (SCFA)-producing bacteria in the intestine. In conclusion, UA possessed a cholesterol-lowering activity and could favorably modulate the gut microbiota.

Study on the interaction between catechin and cholesterol by the density functional theory

Catechin – a natural polyphenol substance – has excellent antioxidant properties for the treatment of diseases, especially for cholesterol lowering. Catechin can reduce cholesterol content in micelles by forming insoluble precipitation with cholesterol, thereby reducing the absorption of cholesterol in the intestine. In this study, to better understand the molecular mechanism of catechin and cholesterol, we studied the interaction between typical catechins and cholesterol by the density functional theory. Results show that the adsorption energies between the four catechins and cholesterol are obviously stronger than that of cholesterol themselves, indicating that catechin has an advantage in reducing cholesterol micelle formation. Moreover, it is found that the molecular interactions of the complexes are mainly due to charge transfer of the aromatic rings of the catechins as well as the hydrogen bond interactions. Unlike the intuitive understanding of a complex formed by hydrogen bond interaction, which is positively correlated with the number of hydrogen bonds, the most stable complexes (epicatechin–cholesterol or epigallocatechin–cholesterol) have only one but stronger hydrogen bond, due to charge transfer of the aromatic rings of catechins.

The cholesterol-lowering activity of miracle fruit (Synsepalum dulcificum)

Miracle fruit (Synsepalum dulcificum) is famous for its uniqueness of modifying sour taste to sweetness. However, its cholesterol-lowering activity has not been reported. This study investigated the effect of S. dulcificum on the compositional changes of plasma lipids in hamsters fed a high-cholesterol control diet. Six groups of hamsters were fed either a control diet or one of the five experimental diets containing 2% ethanol extract of leaves, 2% water extract of leaves, 2% ethanolic extract of seeds (ES), 2% water extract of seeds, or 2% dry pulp. Results showed that ES decreased the plasma total cholesterol (TC). Two triterpenoids (lupeol acetate and β-amyrin acetate) were isolated from the ES and they added to a diet could decrease TC by 15%-20% in hamsters. It was concluded that ES showed potent TC-lowering activity and triterpenoid was one of the active components of ES. PRACTICAL APPLICATIONS: In recent years, people are more interested in phytochemicals from functional foods treated for hyperlipidemia because they possessed fewer side effects than the synthetic drugs. The triterpenoids isolated from the miracle fruit may be promising candidates for the development of cholesterol-lowering agent, especially for patients whose blood cholesterol level and body weight are high. Meanwhile, the miracle fruit have a good potential as cholesterol-lowering functional food or a natural source of cholesterol-lowering agent.

Structure and diversity of 13S globulin zero-repeat subunit, the trypsin-resistant storage protein of common buckwheat (Fagopyrum esculentum M.) seeds

The zero-repeat subunit of 13S globulin, which lacks tandem repeat inserts, is trypsin-resistant and suggested to show higher allergenicity than the other subunits in common buckwheat (Fagopyrum esculentum Moench). To evaluate allelic variations and find novel alleles, the diversity of the zero-repeat genes was examined for two Japanese elite cultivars and 15 Pakistani landraces. The results demonstrated that two new alleles GlbNA1 and GlbNC1, plus three additional new alleles GlbNA2, GlbNA3, and GlbND, were identified besides the already-known GlbNA, GlbNB, and GlbNC alleles. In the Pakistani landraces, GlbNA was the most dominant allele (0.60-0.88 of allele frequency) in all except one landrace, where GlbNB was the most dominant allele (0.50 of allele frequency). Similar to GlbNC, the alleles GlbNA2 and GlbNA3 had extra ~200 bp MITE-like sequences around the stop codon. Secondary structure predictions of a sense strand demonstrated that the extra ~200 bp sequences of GlbNC, GlbNA2, and GlbNA3 can form rigid hairpin structures with free energies of -78.95, -67.06, and -29.90 kcal/mol, respectively. These structures may affect proper transcription and/or translation. In the GlbNC homozygous line, no transcript of a zero-repeat gene was detected, suggesting the material would be useful for developing hypoallergenic buckwheat.

Wild Melon Seed Oil Reduces Plasma Cholesterol and Modulates Gut Microbiota in Hypercholesterolemic Hamsters

Wild melon (Cucumis melo var. agrestis) seed oil (CO) contains 71.3% polyunsaturated fatty acids. The present study investigated the effects of CO on blood cholesterol and gut microbiota. Hamsters (n = 32) were randomly divided into four groups and given one of four diets, namely noncholesterol diet (NCD), high-cholesterol diet containing 0.1% cholesterol (HCD), HCD containing 4.75% CO (COL), and HCD containing 9.5% CO (COH) for 6 weeks. CO supplementation at 9.5% in the diet reduced plasma cholesterol by 24% and enhanced the excretion of fecal bile acids by 150%. CO supplementation upregulated the gene expression of hepatic cholesterol 7α-hydroxylase (CYP7A1). In addition, supplementation of CO in the diet remarkably increased the production of fecal short-chain fatty acids and favorably altered the relative abundances of Eubacteriaceae, Clostridiales_vadinBB60_group, Ruminococcaceae, Streptococcaceae, and Desulfovibrionaceae at a family level. It was concluded that CO could reduce plasma cholesterol via promoting the excretion of fecal acidic sterols and modulating gut microbiota.

In Vitro Hypocholesterolemic Effect of Coffee Compounds

(1) Background: Cholesterol bioaccessibility is an indicator of cholesterol that is available for absorption and therefore can be a measure of hypocholesterolemic potential. In this work, the effect of commercial espresso coffee and coffee extracts on cholesterol solubility are studied in an in vitro model composed by glycodeoxycholic bile salt, as a measure of its bioaccessibility. (2) Methods: Polysaccharide extracts from coffees obtained with different extraction conditions were purified by selective precipitation with ethanol, and their sugars content were characterized by GC-FID. Hexane extraction allowed us to obtain the coffee lipids. Espresso coffee samples and extracts were tested regarding their concentration dependence on the solubility of labeled 13C-4 cholesterol by bile salt micelles, using quantitative 13C NMR. (3) Results and Discussion: Espresso coffee and coffee extracts were rich in polysaccharides, mainly arabinogalactans and galactomannans. These polysaccharides decrease cholesterol solubility and, simultaneously, the bile salts' concentration. Coffee lipid extracts were also found to decrease cholesterol solubility, although not affecting bile salt concentration. (4) Conclusions: Coffee soluble fiber, composed by the arabinogalactans and galactomannans, showed to sequester bile salts from the solution, leading to a decrease in cholesterol bioaccessibility. Coffee lipids also decrease cholesterol bioaccessibility, although the mechanism of action identified is the co-solubilization in the bile salt micelles. The effect of both polysaccharides and lipids showed to be additive, representing the overall effect observed in a typical espresso coffee. The effect of polysaccharides and lipids on cholesterol bioaccessibility should be accounted on the formulation of hypocholesterolemic food ingredients.

Tomato seed oil attenuates hyperlipidemia and modulates gut microbiota in C57BL/6J mice

TSO can significantly improve fatty acid metabolism and cholesterol metabolism, thereby inhibiting obesity and hypercholesterolemia. TSO can favorably modulate the gut microbiota.

Dietary citrus peel essential oil ameliorates hypercholesterolemia and hepatic steatosis by modulating lipid and cholesterol homeostasis

Integration of lipidomics and gene expression analysis provided new insights into in-depth mechanistic understanding of the effects of dietary CPEO.

Conjugated linoleic acid regulates lipid metabolism through the expression of selected hepatic genes in laying hens

The effect of dietary conjugated linoleic acid (CLA) supplementation on lipid metabolism in laying hens was investigated. A total of 360 eighteen-wk-old Hy-Line Brown layers were randomly divided into 4 groups that consisted of 6 replicates with 15 birds each. Birds were fed basal diets with 0, 1%, 2%, and 4% CLA addition. The experiment lasted for 56 D after a 7-D adaptation period. Results showed that dietary CLA addition linearly reduced (P < 0.05) abdominal fat percentage but linearly increased (P < 0.05) relative liver weight of layers on day 56. A linear reduction (P < 0.05) in serum low-density lipoprotein cholesterol (LDL-C) level and a linear elevation (P < 0.05) in the ratio of serum high-density lipoprotein cholesterol level to LDL-C level of layers on both days 28 and 56 were observed with dietary CLA addition, which also linearly decreased (P < 0.05) cholesterol content in the liver of layers on day 56 as well as in eggs on both days 28 and 56. Besides, there were linear reductions (P < 0.05) in the gene expression and contents of hepatic 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGR) and cholesterol 7 alpha hydroxylase 1 (CYP7A1), along with a linear increase (P < 0.05) in the gene expression and content of hepatic low-density lipoprotein receptor (LDLR) in layers responded to dietary CLA addition. In conclusion, dietary CLA supplementation decreased the accumulation of lipids including abdominal fat and cholesterol in the liver and egg of laying hens, probably by upregulating hepatic LDLR expression and downregulating hepatic HMGR and CYP7A1 expression.

Fish Oil Is More Potent than Flaxseed Oil in Modulating Gut Microbiota and Reducing Trimethylamine-N-oxide-Exacerbated Atherogenesis

Trimethylamine-N-oxide (TMAO) is a risk factor for atherosclerosis. We compared the potency of fish oil with flaxseed oil in reducing TMAO-exacerbated atherogenesis. Five groups of ApoE^-/- mice were given one of five diets, namely, a low-fat diet, a Western high fat diet (WD), a WD plus 0.2% TMAO, and two WDs containing 0.2% TMAO with 50% lard being replaced by flaxseed oil or fish oil. TMAO accelerated atherosclerosis and disturbed cholesterol homeostasis. Compared with flaxseed oil, fish oil was more effective in inhibiting TMAO-induced atherogenesis by lowering plasma cholesterol and inflammatory cytokines. Both oils could reverse TMAO-induced decrease in fecal acidic sterols. Fish oil promoted fecal output of neutral sterols and downregulated hepatic cholesterol biosynthesis. Fish oil was more effective than flaxseed oil in promoting the growth of short-chain fatty acid-producing bacteria and lowering microbial generation of lipopolysaccharide. In conclusion, fish oil is more potent than flaxseed oil to ameliorate TMAO-exacerbated atherogenesis.

Oral Administration of Succinoglycan Riclin Improves Diet-Induced Hypercholesterolemia in Mice

Epidemiological studies have demonstrated that hypercholesterolemia is associated with an elevated risk of atherosclerosis and cardiovascular diseases. In addition to the available cholesterol-lowering drugs, nutritionally balanced diets containing functional foods have attracted much interest as potential candidates to improve hypercholesterolemia. In the study, we demonstrated that dietary succinoglycan riclin effectively alleviated diet-induced hypercholesterolemia. Compared with the high-cholesterol-diet (HCD) group, the high-riclin group significantly decreased levels of the serum total cholesterol, low-density lipoprotein cholesterol (LDL-C), and hepatic cholesterol (34, 40, and 51%, respectively), consequently improving hepatic steatosis and reducing proinflammatory cytokine expressions. ¹H nuclear magnetic resonance (NMR)-based lipidomics and metabolomics analyses revealed that the riclin group partially reversed metabolic profile changes induced by the HCD, approaching that of the normal diet (ND) group. Riclin has no direct effects on cholesterol metabolism-related gene expression among the three HCD model groups. Basically, riclin increased the solution viscosity and interfered in the process of bile acid-cholesterol emulsification, decreasing cholesterol digestion and promoting cholesterol and bile acid excretion in the feces. These results suggested potential therapeutic utility of succinoglycan riclin as a food additive for people suffering from hypercholesterolemia and related diseases.

Fruit Seeds as Sources of Bioactive Compounds: Sustainable Production of High Value-Added Ingredients from By-Products within Circular Economy

The circular economy is an umbrella concept that applies different mechanisms aiming to minimize waste generation, thus decoupling economic growth from natural resources. Each year, an estimated one-third of all food produced is wasted; this is equivalent to 1.3 billion tons of food, which is worth around US$1 trillion or even $2.6 trillion when social and economic costs are included. In the fruit and vegetable sector, 45% of the total produced amount is lost in the production (post-harvest, processing, and distribution) and consumption chains. Therefore, it is necessary to find new technological and environmentally friendly solutions to utilize fruit wastes as new raw materials to develop and scale up the production of high value-added products and ingredients. Considering that the production and consumption of fruits has increased in the last years and following the need to find the sustainable use of different fruit side streams, this work aimed to describe the chemical composition and bioactivity of different fruit seeds consumed worldwide. A comprehensive focus is given on the extraction techniques of water-soluble and lipophilic compounds and in vitro/in vivo functionalities, and the link between chemical composition and observed activity is holistically explained.

Improvement of phytochemical production by plant cells and organ culture and by genetic engineering

Plants display an amazing ability to synthesize a vast array of secondary metabolites that are an inexhaustible source of phytochemicals, bioactive molecules some of which impact the human health. Phytochemicals present in medicinal herbs and spices have long been used as natural remedies against illness. Plant tissue culture represents an alternative to whole plants as a source of phytochemicals. This approach spares agricultural land that can be used for producing food and other raw materials, thus favoring standardized phytochemical production regardless of climatic adversities and political events. Over the past 20 years, different strategies have been developed to increase the synthesis and the extraction of phytochemicals from tissue culture often obtaining remarkable results. Moreover, the availability of genomics and metabolomics tools, along with improved recombinant methods related to the ability to overexpress, silence or disrupt one or more genes of the pathway of interest promise to open new exciting possibilities of metabolic engineering. This review provides a general framework of the cellular and molecular tools developed so far to enhance the yield of phytochemicals. Additionally, some emerging topics such as the culture of cambial meristemoid cells, the selection of plant cell following the expression of genes encoding human target proteins, and the bioextraction of phytochemicals from plant material have been addressed. Altogether, the herein described techniques and results are expected to improve metabolic engineering tools aiming at improving the production of phytochemicals of pharmaceutical and nutraceutical interest.