Cholesterol transporter proteins in HepG2 cells can be modulated by phenolic compounds present in Opuntia ficus-indica aqueous solutions

The Hypocholesterolemic Potential of the Edible Algae Fucus vesiculosus: Proteomic and Quantitative PCR Analysis

A brown seaweed consumed worldwide, Fucus vesiculosus, has been used to prevent atherosclerosis and hypercholesterolemia, among other uses. However, the mechanisms of action that lead to these effects are not yet fully understood. This work aims to study the in vitro effect of an aqueous extract of F. vesiculosus, previously characterized as rich in phlorotannins and peptides, on the expression of different proteins involved in the synthesis and transport of cholesterol. A proteomic analysis, Western blot, and qRT-PCR analysis were performed to identify protein changes in HepG2 cells exposed to 0.25 mg/mL of the F. vesiculosus extract for 24 h. The proteomic results demonstrated that, in liver cells, the extract decreases the expression of four proteins involved in the cholesterol biosynthesis process (CYP51A1, DHCR24, HMGCS1 and HSD17B7). Additionally, a 12.76% and 18.40% decrease in the expression of two important transporters proteins of cholesterol, NPC1L1 and ABCG5, respectively, was also observed, as well as a 30% decrease in NPC1L1 mRNA levels in the cells exposed to the extract compared to control cells. Our study reveals some of the mechanisms underlying the actions of bioactive compounds from F. vesiculosus that may explain its previously reported hypocholesterolemic effect, future prospecting its use as a functional food.

Anti-Hypercholesterolemia Effects of Edible Seaweed Extracts and Metabolomic Changes in Hep-G2 and Caco-2 Cell Lines

Hypercholesterolemia is a major risk for the development of cardiovascular diseases (CVDs), the main cause of mortality worldwide, and it is characterized by high levels of circulating cholesterol. The drugs currently available for hypercholesterolemia control have several side effects, so it is necessary to develop new effective and safer therapies. Seaweeds serve as sources of several bioactive compounds with claimed beneficial effects. Eisenia bicyclis (Aramé) and Porphyra tenera (Nori) are edible seaweeds that were previously recognized as rich in bioactive compounds. In the present study, we aim to evaluate the anti-hypercholesterolemia effect of these two seaweed extracts and their health potential. Both extracts, but more efficiently Aramé extract, have liver 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGR) inhibitory activity as well as the capability to reduce approximately 30% of cholesterol permeation through human Caco-2 cells by simulating the intestinal lining, which is a target for hypercholesterolemia treatments. An untargeted metabolomic assay on human intestinal Caco-2 and liver Hep-G2 cell lines exposed to Aramé and Nori extracts revealed changes in the cells' metabolism, indicating the extracts' health beneficial effects. The metabolic pathways affected by exposure to both extracts were associated with lipid metabolism, such as phospholipids, and fatty acid metabolism, amino acid pathways, cofactors, vitamins, and cellular respiration metabolism. The effects were more profound in Aramé-treated cells, but they were also observed in Nori-exposed cells. The metabolite modifications were associated with the protection against CVDs and other diseases and to the improvement of the cells' oxidative stress tolerance. The results obtained for the anti-hypercholesterolemia properties, in addition to the revelation of the positive impact on cell metabolism, offer an important contribution for further evaluation of these seaweed extracts as functional foods or for CVD prevention.

An overview and update on the chemical composition and potential health benefits of Opuntia ficus-indica (L.) Miller

Opuntia ficus-indica (OFI), widely recognized as prickly pear, is native to Mexico and it is distributed in many areas of the world because of its socioeconomic, agronomic, and ecological benefits, besides its large amounts of functional, nutraceutical, and biological activities. Various parts of this plant including the fruit pulp and peel, cladode, and seeds are scientifically proven to have therapeutic potentials and are safe for human use. The contents of phytochemical compounds in each part of the OFI are different. Each pharmacological activity depends on the phytochemical compounds, the components used, and the extraction type. In this review, we summarize the active constituents from different parts of OFI and their pharmacological effects including the antioxidant, wound healing, skin protective, hepatoprotective, anticancer, antidiabetic, antihypercholesterolemic, and anti-obesity activities. Besides its effects on the bone health, cardiovascular system, kidneys, and gastrointestinal tract, its gastroprotective, anti-ulcer, anti-inflammatory, antiviral, neuroprotective, sedative, analgesic, anxiolytic and antimicrobial effects and effects on cognitive and memory function are also mentioned. PRACTICAL APPLICATIONS: Over the past few decades, the health benefits of Opuntia ficus-indica (OFI) have received much attention. All parts of the plant, including the fruit pulp and peel, cladode, and seeds have found use in the treatment of many diseases. The chemical composition of OFI provides both a high nutritional value and various health benefits. Therefore, the aim of this review is to present the up-to-date research carried out on OFI phytochemicals, showing the most important biological activities reported.

Hydroxycinnamic acid derivatives effect on hypercholesterolemia, comparison with ezetimibe: Permeability assays and FTIR spectroscopy on Caco-2 cell line

High blood cholesterol levels may increase the risk of developing atherosclerosis. Since intestinal cholesterol absorption plays a major role in maintaining total body cholesterol homeostasis, the aim of the present study was to compare the effect of ezetimibe and three hydroxycinnamic acid derivatives (rosmarinic acid, chlorogenic acid and m-coumaric acid) that are present in several medicinal plants on cholesterol absorption in the intestinal Caco-2 ​cells. In addition to the permeability assays, studies on alteration of the biochemical properties of Caco-2 ​cells under the effect of ezetimibe and hydroxycinnamic acid derivatives was evaluated using FTIR accompanied with multivariate analysis by PCA. The cholesterol permeability assays showed that these compounds could decrease cholesterol permeability with a percentage ranging from 76.98 to 96.6% with the highest inhibition for ezetimibe. whereas the FTIR studies didn't show similar changes between ezetimibe and the three hydroxycinnamic acid derivatives in protein and nucleic acids region, suggesting that these compounds have hypocholesterolemic effect. Nevertheless, each compound originated a different change on Caco-2 treated cells suggesting a different mode of action.

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Hydroxycinnamic acid derivatives and ezetimibe permeated the intestinal barrier.

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Hydroxycinnamic acid derivatives decreased cholesterol permeability.

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Hydroxycinnamic acid derivatives could affect the cell components.

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PCA of FTIR spectra showed differences on protein and nucleic acid regions.

Molecular-level changes induced by hydroxycinnamic acid derivatives in HepG2 cell line: Comparison with pravastatin

Hydroxycinnamic acid derivatives are an important class of polyphenols found in fruits, vegetables, and medicinal plants and widely consumed in human diet. In the present work, alterations of HepG2 cells biochemical profile under the effect of four hydroxycinnamic acid derivatives (caffeic acid, m-coumaric acid, chlorogenic acid and rosmarinic acid) relatively to the effect of pravastatin, a drug often prescribed to inhibit HMG-CoA reductase enzyme, the regulator enzyme in the cholesterol biosynthesis pathway, were reported. The application of FTIR spectroscopy in combination with multivariate analysis by PCA showed a similarity between pravastatin and the four hydroxycinnamic acid derivatives in metabolite profile modification expressed by various changes in proteins region, the phosphate region which mainly corresponds to nucleic acids as well as in lipids regions. FTIR structural analysis in the amide I region, using resolution enhancement methods, such as second derivative and amide I deconvolution method, revealed significant decrease in α-helix/random coil and intermolecular β-sheet decreased while intramolecular β-sheet in treated cells showed an increase. It was also noticed that the intracellular cholesterol as well as esterified ingredients such as cholesterol esters in the cell membrane decreased. Moreover, principal component analysis (PCA) of the spectral data showed that the compounds and pravastatin were well separated from untreated cells showing a different mode of action on HepG2 treated cells for each compound.

Brown Algae Potential as a Functional Food against Hypercholesterolemia: Review

Brown algae have been part of the human diet for hundreds of years, however, in recent years, commercial and scientific interest in brown algae has increased due to the growing demand for healthier diet by the world population. Brown algae and its metabolites, such as carotenoids, polysaccharides, phlorotannins, and proteins, have been associated with multiple beneficial health effects for different diseases, such as cardiovascular diseases, one of the main causes of death in Europe. Since high blood cholesterol levels are one of the major cardiovascular risks, this review intends to provide an overview of current knowledge about the anti-hypercholesterolemic effect of different brown algae species and/or their isolated compounds.

Effect of Food Preparations on In Vitro Bioactivities and Chemical Components of Fucus vesiculosus

Fucus vesiculosus is a brown macroalgae used in food and generally considered safe to be consumed, according to EU Directive (EC 258/97). The aim of this study is to analyze the effect of food preparation on F.vesiculosus of different origins on what concerns its chemical constituents and final bioactivities. The aqueous extract of the seaweeds were obtained at different temperatures, similar to food preparation and then purified by SPE. The compound identification was carried out by Liquid Chromatography High Resolution Mass Spectrometry (LC-HRMS/MS) and algae extracts microstructure were observed by Scanning Electron Microscopy (SEM). The activities were determined by using antioxidant activity, inhibition of acetylcholinesterase (AChE) and 3-hidroxi-3-methyl-glutaril-CoA (HMG-CoA) reductase (HMGR) together with Caco-2 cells line simulating the intestinal barrier. The activity of AChE and the HMGR were inhibited by the extracts giving IC₅₀ values of 15.0 ± 0.1 µg/mL and 4.2 ± 0.1 µg/mL, respectively and 45% of the cholesterol permeation inhibition. The main compounds identified were phlorotannins and peptides derivatives. The mode of preparation significantly influenced the final bioactivities. Moreover, the in vitro results suggest that the preparation of F. vesiculosus as a soup could have hypercholesterolemia lowering effect.

Digestive Stability and Bioaccessibility of Antioxidants in Prickly Pear Fruits from the Canary Islands: Healthy Foods and Ingredients

Although prickly pear fruits have become an important part of the Canary diet, their native varieties are yet to be characterized in terms of betalains and phenolic compounds. To exert potential health benefits, these antioxidants must be released from the food matrix and be stable in the gastrointestinal tract. Our aim was to characterize the betalain and phenolic profile of four prickly pear varieties from the Canary Islands (Spain) and determine their digestive stability and bioaccessibility via in vitro gastrointestinal digestion. Digestive studies were performed considering the (i) importance of the edible fraction (pulps) and (ii) potential of fruit peels as by-products to obtain healthy ingredients. Betalains and phenolic profiles were analyzed by HPLC-DAD-ESI/MS and HPLC-DAD-MS/QTOF. Pulps in Colorada and Fresa varieties presented high indicaxanthin and betanin content, respectively. Despite low pH in the gastric phase, betalains were stable to reach the intestinal phase, although indicaxanthin presented a higher bioaccessibility. Blanco Buenavista peels contained a distinct flavonoid profile including a new isorhamnetin-hexosyl-rhamnoside. Phenolic compounds were abundant and highly bioaccessible in fruit peels. These findings suggest that prickly pear pulps are rich in bioaccessible betalains; and that their peels could be proposed as potential by-products to obtain sustainable healthy ingredients.