Sea cucumber-derived compounds for treatment of dyslipidemia: A review

A comparative study of the hypolipidemic effects and mechanisms of action of Laminaria japonica- and Ascophyllum nodosum-derived fucoidans in apolipoprotein E-deficient mice

The structural characteristics of fucoidans exhibit species and regional diversity. Previous studies have demonstrated that Laminaria japonica- and Ascophyllum nodosum-derived fucoidans have type I and type II fucosyl chains, respectively. These chemical differences may contribute to distinct hypolipidemic effects and mechanisms of action. Chemical analysis demonstrated that the percentage contents of sulfate, glucuronic acid, and galactose were higher in L. japonica-derived fucoidans than those of A. nodosum-derived fucoidans. In hyperlipidemic apolipoprotein E-deficient mice, both A. nodosum- and L. japonica-derived fucoidans significantly decreased the plasma and hepatic levels of total cholesterol and triglyceride, leading to the reduction of atherosclerotic plaques. Western blotting experiments demonstrated that these fucoidans significantly enhanced the expression and levels of scavenger receptor B type 1, cholesterol 7 alpha-hydroxylase A1, and peroxisome proliferator-activated receptor (PPAR)-α, contributing to circulating lipoprotein clearance and fatty acid degradation, respectively. Differentially, L. japonica-derived fucoidan significantly increased the LXR/ATP-binding cassette G8 signaling pathway in the small intestine, as revealed by real-time quantitative PCR, which may lead to further cholesterol and other lipid excretion. Collectively, these data are useful for understanding the hypolipidemic mechanisms of action of seaweed-derived fucoidans, and their potential application for the prevention and/or treatment of atherosclerotic cardiovascular diseases.

Berberine modulates cardiovascular diseases as a multitarget-mediated alkaloid with insights into its downstream signals using in silico prospective screening approaches

Atherosclerosis is potentially correlated with several cardiac disorders that are greatly associated with cellular oxidative stress generation, inflammation, endothelial cells dysfunction, and many cardiovascular complications. Berberine is a natural isoquinoline alkaloid compound that widely modulates pathogenesis of atherosclerosis through its different curative potentials. This in silico screening study was designed to confirm the potent restorative properties of berberine chloride as a multitarget-mediated alkaloid against the CVDs and their complications through screening, identifying, visualizing, and evaluating its binding models, affinities, and interactions toward several CVDs-related targets as direct and/or indirect-mediated signals via inhibiting cellular ER stress and apoptotic signals and activating autophagy pathway. The drug-likeness properties of berberine were predicted using the computational QSAR/ADMET and Lipinski's RO5 analyses as well as in silico molecular docking simulations. The potent berberine-binding modes, residues-interaction patterns, and free energies of binding scores towards several CVDs-related targets were estimated using molecular docking tools. Furthermore, the pharmacokinetic properties and toxicological features of berberine were clearly determined. According to this in silico virtual screening study, berberine chloride could restore cardiac function and improve pathogenic features of atherosclerotic CVDs through alleviating ER stress and apoptotic signals, activating autophagy, improving insulin sensitivity, decreasing hyperglycemia and dyslipidemia, increasing intracellular RCT signaling, attenuating oxidative stress and vascular inflammation, and upregulating cellular antioxidant defenses in many cardiovascular tissues. In this in silico study, berberine chloride greatly modulated several potent CVDs-related targets, including SIGMAR1, GRP78, CASP3, BECN1, PIK3C3, SQSTM1/p62, LC3B, GLUT3, INSR, LDLR, LXRα, PPARγ, IL1β, IFNγ, iNOS, COX-2, MCP-1, IL10, GPx1, and SOD3.

Natural products in atherosclerosis therapy by targeting PPARs: a review focusing on lipid metabolism and inflammation

Inflammation and dyslipidemia are critical inducing factors of atherosclerosis. Peroxisome proliferator-activated receptors (PPARs) are ligand-activated transcription factors and control the expression of multiple genes that are involved in lipid metabolism and inflammatory responses. However, synthesized PPAR agonists exhibit contrary therapeutic effects and various side effects in atherosclerosis therapy. Natural products are structural diversity and have a good safety. Recent studies find that natural herbs and compounds exhibit attractive therapeutic effects on atherosclerosis by alleviating hyperlipidemia and inflammation through modulation of PPARs. Importantly, the preparation of natural products generally causes significantly lower environmental pollution compared to that of synthesized chemical compounds. Therefore, it is interesting to discover novel PPAR modulator and develop alternative strategies for atherosclerosis therapy based on natural herbs and compounds. This article reviews recent findings, mainly from the year of 2020 to present, about the roles of natural herbs and compounds in regulation of PPARs and their therapeutic effects on atherosclerosis. This article provides alternative strategies and theoretical basis for atherosclerosis therapy using natural herbs and compounds by targeting PPARs, and offers valuable information for researchers that are interested in developing novel PPAR modulators.

Laminaria japonica Aresch-Derived Fucoidan Ameliorates Hyperlipidemia by Upregulating LXRs and Suppressing SREBPs

Cardiovascular disease (CVD) is the leading cause of morbidity and mortality worldwide, and hyperlipidemia is one major inducing factor of CVD. It is worthy to note that fucoidans are reported to have hypolipidemic activity with species specificity; however, the underlying mechanisms of action are far from clarification. This study is aimed at investigating the plasma lipid-lowering mechanisms of the fucoidan from L. japonica Aresch by detecting the levels of hepatic genes that are involved in lipid metabolism. Our results demonstrated that the fucoidan F3 significantly lowered total cholesterol and triglyceride in C57BL/6J mice fed a high-fat diet. In the mouse liver, fucoidan F3 intervention significantly increased the gene expression of peroxisome proliferator-activated receptor (PPAR) α, liver X receptor (LXR) α and β, and ATP-binding cassette transporter (ABC) G1 and G8 and decreased the expression of proprotein convertase subtilisin/kexin type 9 (PCSK9), low-density lipoprotein receptor, cholesterol 7 alpha-hydroxylase A1, and sterol regulatory element-binding protein (SREBP) 1c and SREBP-2. These results demonstrated that the antihyperlipidemic effects of fucoidan F3 are related to its activation of PPARα and LXR/ABC signaling pathways and inactivation of SREBPs. In conclusion, fucoidan F3 may be explored as a potential compound for prevention or treatment of lipid disorders.

Patterns of the Nutrients and Metabolites in Apostichopus japonicus Fermented by Bacillus natto and Their Ability to Alleviate Acute Alcohol Intoxication

The aim of this study was to understand the changes in nutrient composition and differences in metabolites in Apostichopus japonicus fermented by Bacillus natto and their function in alleviating acute alcohol intoxication (AAI) through in vivo studies. The results showed no significant difference between the basic components of sea cucumber (SC) and fermented sea cucumber (FSC). The SC proteins were degraded after fermentation, and the amino acid content in FSC was significantly increased. The differentially abundant metabolites of SC and FSC were identified by LC-MS/MS. The contents of amino acid metabolites increased after fermentation, and arachidonic acid metabolism was promoted. The results demonstrated that FSC alleviated AAI by improving the activities of alcohol-metabolizing enzymes and antioxidant enzymes in the liver but did not alleviate the accumulation of triglycerides. Our results will provide beneficial information for the development and application of new products from FSC.

Structure, in vitro digestive characteristics and effect on gut microbiota of sea cucumber polysaccharide fermented by Bacillus subtilis Natto

This study aimed to understand the structural, digestion and fecal fermentation behaviors of sea cucumber polysaccharide fermented by Bacillus subtilis Natto. Results showed that both sea cucumber polysaccharide (SP) and fermented sea cucumber polysaccharide (FSP) were sulfated polysaccharides mainly containing fucose. The physicochemical property, molecular weight, thermal property, and functional groups were no significant difference between SP and FSP, but the microscopic morphology and monosaccharide composition of FSP changed. Both SP and FSP showed similar digestion and fecal fermentation characteristics, that is, they could not be digested by saliva and gastric juice, but could be partially degraded by small intestine. Due to the decomposition of glycosidic bonds after intestinal digestion and fecal fermentation, the relative molecular mass of SP and FSP decreased. In terms of impacts on gut microbiota, Lachnospira, Bacteroides finegoldii, and Bifidobacteriaceae were significantly increased in SP, while Acinetobacter was significantly increased in FSP. This study provides a good understanding of the changes in the structure and digestive characteristics of sea cucumber polysaccharides caused by fermentation. That information will be beneficial for the development and application of new fermented sea cucumber products.

Saponins of North Atlantic Sea Cucumber: Chemistry, Health Benefits, and Future Prospectives

Frondosides are the major saponins (triterpene glycosides) of the North Atlantic sea cucumber (Cucumaria frondosa). Frondosides possess amphiphilic characteristics due to the presence of various hydrophilic sugar moieties and hydrophobic genin (sapogenin). Saponins are abundant in holothurians, including in sea cucumbers that are widely distributed across the northern part of the Atlantic Ocean. Over 300 triterpene glycosides have been isolated, identified, and categorized from many species of sea cucumbers. Furthermore, specific saponins from sea cucumbers are broadly classified on the basis of the fron-dosides that have been widely studied. Recent studies have shown that frondoside-containing extracts from C. frondosa exhibit anticancer, anti-obesity, anti-hyperuricemic, anticoagulant, antioxidant, antimicrobial, antiangiogenic, antithrombotic, anti-inflammatory, antitumor, and immunomodulatory activities. However, the exact mechanism(s) of action of biological activities of frondosides is not clearly understood. The function of some frondosides as chemical defense molecules need to be understood. Therefore, this review discusses the different frondosides of C. frondosa and their potential therapeutic activities in relation to the postulated mechanism(s) of action. In addition, recent advances in emerging extraction techniques of frondosides and other saponins and future perspectives are discussed.