Proteoglycan isolated from Corbicula fluminea exerts hepato-protective effects against alcohol-induced liver injury in mice

Comparative study on the anti-alcoholic liver disease efficiency of the ethanol- and water-soluble polysaccharides from Baijiu vinasses

Ethanol- and water-soluble polysaccharides were extracted from Baijiu vinasses (EP and WP), respectively. EP was dominantly composed by arabinose, glucose and xylose with molar ratio of 8.81: 76.82: 6.9. While, WP was dominantly composed by galactose, glucose and mannose with molar ratio of 8.32: 56.05: 25.19. The molecular weights and reducing sugar contents in EP and WP were 6.2 kDa vs. 16.1 kDa and 24.52 ± 0.97 % vs. 19.77 ± 0.75 %, respectively. Alterations in activation of the Nrf2/HO-1 signalling pathway and increases in the abundance of Lachnospiraceae and Akkermansia and their associated metabolisms could be the general mechanism by which Baijiu vinasses (BV) polysaccharides alleviated alcohol-induced liver disease (ALD) in mice. Due to the different physicochemical characteristics, the ALD alleviation efficiency was different. EP exhibited higher efficiency in oxidative stress suppressing and lipid alternation by activating the peroxisome proliferators-activated receptors (PPAR) signalling pathway. WP exhibited higher efficiency in liver damage repairing with the controlment in tryptophan metabolism pathway. This study exhibited the potential biofunction of BV polysaccharides in ALD alleviation and could promote the BV upcycling.

Multidisciplinary structural optimization of polysaccharides preventing alcohol-induced liver disease with computer-aided molecular design

Here, we optimized the active units of polysaccharides and investigated the conformational relationship between the polysaccharides and alcoholic liver disease (ALD) at the molecular level. We used data mining to screen polysaccharide structural parameters for ALD (PSP-ALD). Most ALD-resistant polysaccharides against ALD comprised glucose (Glc), mannose (Man), galactose (Gal), arabinose (Ara), and rhamnose (Rha). Additionally, (1 → 6)-, (1 → 3)-, and (1 → 4)- glycosidic linkages were mainly contained. Polysaccharides against ALD have a wide molecular weight distribution (2.1 × 103 Da - 9.6 × 107 Da). Based on the PSP-ALD analysis, six commercially available oligosaccharides were selected and their structures were built. After molecular docking, the binding affinities between stachyose and the key ALD targets were stronger, indicating that stachyose may be a polysaccharide-active unit against ALD (PAU-ALD). Furthermore, histological examination of liver tissue combined with serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and triglycerides (TG) showed that stachyose had a significant protective effect against ALD in mice. In summary, we optimized a PAU-ALD and developed a method for studying the structure-activity relationship between polysaccharides and ALD at the molecular level, which provides a new research direction for the development and utilization of polysaccharides and their clinical applications in ALD.

Effects of Mactra chinenesis Peptides on Alcohol-Induced Acute Liver Injury and Intestinal Flora in Mice

Food-borne bioactive peptides have shown promise in preventing and mitigating alcohol-induced liver injury. This study was the first to assess the novel properties of Mactra chinenesis peptides (MCPs) in mitigating acute alcoholic liver injury in mice, and further elucidated the underlying mechanisms associated with this effect. The results showed that MCPs can improve lipid metabolism by modulating the AMPK signaling pathway, decreasing fatty acid synthase activity, and increasing carnitine palmitoyltransferase 1a activity. Meanwhile, MCPs ameliorate inflammation by inhibiting the NF-κB activation, leading to reduced levels of pro-inflammatory cytokines (tumor necrosis factor-α and interleukin-1β). Additionally, a 16S rDNA sequencing analysis revealed that MCPs can restore the balance of gut microbiota and increase the relative abundance of beneficial bacteria. These findings suggest that supplementation of MCPs could attenuate alcohol intake-induced acute liver injury, and, thus, may be utilized as a functional dietary supplement for the successful treatment and prevention of acute liver injury.

The Synergistic Effects of Corbicula fluminea and Sarcodia montagneana on Alleviating Systemic Inflammation and Osteoarthritis Progression

Osteoarthritis (OA) is a progressive disease that causes pain, stiffness, and inflammation in the affected joints. Currently, there are no effective treatments for preventing the worst outcomes, such as synovitis or cartilage degradation. Sarcodia montagneana and Corbicula fluminea are common species found in the ocean or in freshwater areas. Their extracts are demonstrated to possess both antioxidative and anti-inflammatory functions. This study aimed to investigate the synergistic effects of the extracts of Sarcodia montagneana (SME) and Corbicula fluminea (FCE) on reducing local and systemic inflammation, as well as their efficacy in OA symptom relief. An in vitro monocytic LPS-treated THP-1 cell model and in vivo MIA-induced mouse OA model were applied, and the results showed that the combinatory usage of SME and FCE effectively suppressed IFN-γ and TNF-α production when THP-1 cells were treated with LPS. SME and FCE also significantly decreased the systemic TNF-α level and joint swelling and prevented the loss of proteoglycan in the cartilage within the joints of OA mice. The data shown here provide a potential solution for the treatment of osteoarthritis.

Effect of natural polysaccharides on alcoholic liver disease: A review

In this study, we systematically collected relevant literature in the past five years on the intervention of natural polysaccharides in alcoholic liver disease (ALD) and reviewed the pharmacological activities and potential mechanisms of action. Natural polysaccharides are effective in preventing liver tissue degeneration, inhibiting the alcohol-induced expression of inflammatory factors, inactivation of antioxidant enzymes, and abnormal hepatic lipid deposition. Natural polysaccharides regulate the expression of proteins, such as tight junction proteins, production of small molecule metabolites, and balance of intestinal flora in the intestinal tract to alleviate ALD. Natural polysaccharides also exert therapeutic effects by modulating inflammatory, oxidative, lipid metabolism, and other pathways in the liver. Natural polysaccharides also inhibit alcohol-induced intestinal abnormalities by regulating intestinal flora and feeding back into the liver via the gut-liver axis. However, existing research on natural polysaccharides has many shortcomings: for example, most of the natural polysaccharides for testing are total polysaccharides or crude polysaccharides, progress in research on in vivo metabolic processes and mechanisms is slow, and the degree of industrialisation is insufficient. Finally, we discuss the difficulties in studying natural polysaccharides and future directions to provide a theoretical basis for their development and application.

Bioactivity of polysaccharides derived from bivalves

Bivalves have high diversity, widely distributed in various aquatic environments, including saltwater, brackish water and freshwater. Bivalves are known to rich in polysaccharides and have wide applications in functional foods, pharmaceuticals, and industrial research. Despite many relevant reports are available, the information is poorly organized. Therefore, in this study, we conducted a comprehensive scientific review on the potential bioactivity of polysaccharides derived from bivalves. In general, the polysaccharides derived from bivalves possess various bioactive properties, including anticancer, antioxidant, anticoagulant and immunomodulatory activities. The bioactivity of these biomolecules highly depends on the bivalve species, extraction methods, purification methods, dosages, etc. The information in this study can provide an overview of the bioactivities of bivalve polysaccharides. This is very useful to be used as a guide for identifying the health benefits of polysaccharides derived from different bivalve species.

Protective Effect of Polyphenols, Protein, Peptides, and Polysaccharides on Alcoholic Liver Disease: A Review of Research Status and Molecular Mechanisms

Alcoholic liver disease (ALD) has emerged as an important public health problem in the world. The polyphenols, protein, peptides, and polysaccharides have attracted attention for prevention or treatment of ALD. Therefore, this paper reviews the pathogenesis of ALD, the relationship between polyphenols, peptides, polysaccharides, and ALD, and expounds the mechanism of gut microbiota on protecting ALD. It is mainly found that the hydroxyl group of polyphenols endows it with antioxidation to protect ALD. The ALD protection of bioactive peptides is related to amino acid composition. The ALD protection of polysaccharides is related to the primary structure. Meanwhile, polyphenols, protein, peptides, and polysaccharides prevent or treat ALD by antioxidation, anti-inflammatory, antiapoptosis, lipid metabolism, and gut microbiota regulation. This contribution provides updated information on polyphenols, protein, peptides, and polysaccharides in response to ALD, which will not only facilitate the development of novel bioactive components but also the future application of functional food raw materials will be promoted.

Structural characteristics and ameliorative effect of a polysaccharide from Corbicula fluminea industrial distillate against acute liver injury induced by CCl4 in mice

Corbicula fluminea distillate as an important industrial by-product of C. fluminea during steaming process is rich in amino acids, proteins and polysaccharides, showing potential hepatoprotective effect. In this study, a polysaccharide (CFDP) was obtained from C. fluminea distillate by three-phase partitioning combined with (NH₄)₂SO₄ precipitation at a saturation of 60 %. The structural characteristics, antioxidant activity in vitro, and hepatoprotection against mice CCl₄-induced acute liver damage of CFDP were studied. Results demonstrated that CFDP was a water-soluble homogenous polysaccharide predominantly comprising glucose (>98 %), with a weight-average molecular weight of 1.4 × 10⁷ Da, and exhibiting potent antioxidant benefits in vitro. CFDP had a backbone of (1 → 4)-α-d-glucopyranosyl (Glcp) and a small amount of (1 → 4, 6)-α-D-Glcp. The branch formed at C-6 comprised by (1→)-α-D-Glcp and (1→)-α-D-N-acetylglucosamine. CFDP possessed excellent hepatoprotective activity against acute liver damage caused by CCl₄ in mice, mainly by ameliorating weight reduction and organ injures, alleviating hepatic function and serum lipid metabolism, suppressing oxidative stress and inflammatory responses, as directly verified by histopathological examination. Moreover, CFDP improved gut microbiota by up-regulating the relative abundance of total bacteria and probiotics such as Firmicutes, Bacteroidete, Rumminococcaceae, Lactobacillaceae, accompanied by promoting short chain fatty acid production. Therefore, our findings indicated that CFDP can be developed as a healthy food supplement for the prevention of chemical livery injury.

Structural elucidation and anti-inflammatory activity of a proteoglycan from spent substrate of Lentinula edodes

A proteoglycan LEPS1 was firstly isolated and purified from the spent substrate of Lentinula edodes, an agricultural waste that may cause environmental pollution. The average molecular weight of LEPS1 was 1.18 × 10⁴ g/mol, and carbohydrate moiety (88.9 %) was composed of glucose, arabinose, galactose, xylose and mannose at a molar ratio of 1.2:1.2:1.0:2.3:1.1. The protein moiety (8.5 %) of LEPS1 was bonded to the polysaccharide chain via O-glycosidic linkage. LEPS1 could significantly improve the inflammatory injury of LPS stimulated RAW264.7 macrophages by inhibiting the secretion of NO and decreasing the levels of pro-inflammatory factors (TNF-α, IL-1β and IL-6). LEPS1 inhibited JAK-STAT1 and p38 MAPK signaling pathway via modulating JAK expression, phosphorylation of STAT1 and phosphorylation of p38, respectively. Moreover, LEPS1 could promote the expression of CD 206 and IL-10 which were the markers for repairing macrophages. Overall, LEPS1 had anti-inflammatory activity and can potentially treat as a novel anti-inflammation agent. This work could provide scientific basis and valuable information for the highly efficient utilization of spent L. edodes substrates as the by-product in mushroom industries.

A global synthesis of ecosystem services provided and disrupted by freshwater bivalve molluscs

Identification of ecosystem services, i.e. the contributions that ecosystems make to human well-being, has proven instrumental in galvanising public and political support for safeguarding biodiversity and its benefits to people. Here we synthesise the global evidence on ecosystem services provided and disrupted by freshwater bivalves, a heterogenous group of >1200 species, including some of the most threatened (in Unionida) and invasive (e.g. Dreissena polymorpha) taxa globally. Our systematic literature review resulted in a data set of 904 records from 69 countries relating to 24 classes of provisioning (N = 189), cultural (N = 491) and regulating (N = 224) services following the Common International Classification of Ecosystem Services (CICES). Prominent ecosystem services included (i) the provisioning of food, materials and medicinal products, (ii) knowledge acquisition (e.g. on water quality, past environments and historical societies), ornamental and other cultural contributions, and (iii) the filtration, sequestration, storage and/or transformation of biological and physico-chemical water properties. About 9% of records provided evidence for the disruption rather than provision of ecosystem services. Synergies and trade-offs of ecosystem services were observed. For instance, water filtration by freshwater bivalves can be beneficial for the cultural service 'biomonitoring', while negatively or positively affecting food consumption or human recreation. Our evidence base spanned a total of 91 genera and 191 species, dominated by Unionida (55% of records, 76% of species), Veneroida (21 and 9%, respectively; mainly Corbicula spp.) and Myoida (20 and 4%, respectively; mainly Dreissena spp.). About one third of records, predominantly from Europe and the Americas, related to species that were non-native to the country of study. The majority of records originated from Asia (35%), with available evidence for 23 CICES classes, as well as Europe (29%) and North America (23%), where research was largely focused on 'biomonitoring'. Whilst the earliest record (from 1949) originated from North America, since 2000, annual output of records has increased rapidly in Asia and Europe. Future research should focus on filling gaps in knowledge in lesser-studied regions, including Africa and South America, and should look to provide a quantitative valuation of the socio-economic costs and benefits of ecosystem services shaped by freshwater bivalves.

A review on shellfish polysaccharides: Extraction, characterization and amelioration of metabolic syndrome

Shellfish are diverse, widely distributed organisms that are a rich source of biological resources. Polysaccharides are an important components in shellfish, hence a great deal of attention has been directed at isolation and characterization of shellfish polysaccharides because of their numerous health benefits. Differences in shellfish species, habits, and environment result in the diversity of the structure and composition of polysaccharides. Thus, shellfish polysaccharides possess special biological activities. Studies have shown that shellfish polysaccharides exert biological activities, including antioxidant, antitumor, immune-regulation, hypolipidemic, antihypertensive, and antihyperglycemic effects, and are widely used in cosmetics, health products, and medicine. This review spotlights the extraction and purification methods of shellfish polysaccharides and analyses their structures, biological activities and conformational relationships; discusses the regulatory mechanism of shellfish polysaccharides on hyperlipidemia, hypertension, and hyperglycemia caused by lipid metabolism disorders; and summarizes its alleviation of lipid metabolism-related diseases. This review provides a reference for the in-depth development and utilization of shellfish polysaccharides as a functional food to regulate lipid metabolism-related diseases. To achieve high value utilization of marine shellfish resources while actively promoting the development of marine biological industry and health industry.

New understanding of Angelica sinensis polysaccharide improving fatty liver: The dual inhibition of lipid synthesis and CD36-mediated lipid uptake and the regulation of alcohol metabolism

Angelica sinensis polysaccharide (ASP) has presented increasingly recognized lipid regulation and antioxidant abilities. However, there is little direct evidence to explain why ASP possesses the observed lipid-lowering and anti-oxidation effects. In vivo and in vitro models of alcoholic fatty liver disease (AFLD) were established to examine the direct effect of ASP on hepatic fat accumulation. Our results showed that the lipid-lowering effect of ASP might result from the dual inhibition of lipid synthesis and CD36-mediated lipid uptake. The antioxidation of ASP might be attributed to the reversal of alcohol metabolic pathways from CYP2E1 catalysis to ADH catalysis. Taken together, the study demonstrated the direct role of ASP in lipid metabolism for the first time and revealed the underlying mechanism of reducing ROS, providing an available strategy for ASP as a potential agent to treat AFLD.

Hepatoprotective effects of sea cucumber ether-phospholipids against alcohol-induced lipid metabolic dysregulation and oxidative stress in mice

Sea cucumber is widely consumed as food and folk medicine in Asia, and its phospholipids are rich sources of dietary eicosapentaenoic acid enriched ether-phospholipids (ether-PLs). Emerging evidence suggests that ether-PLs are associated with neurodegenerative disease and steatohepatitis. However, the function and mechanism of ether-PLs in alcoholic liver disease (ALD) are not well understood. To this end, the present study sought to investigate the hepatoprotective effects of sea cucumber ether-PLs, including plasmenyl phosphatidylethanolamine (PlsEtn) and plasmanyl phosphatidylcholine (PlsCho), and their underlying mechanisms. Our results showed that compared with EtOH-induced mice, ether-PL treated mice showed improved liver histology, decreased serum ALT and AST levels, and reduced alcohol metabolic enzyme (ALDH2 and ADH1) expressions. Mechanistic studies showed that ether-PLs attenuated "first-hit" hepatic steatosis and lipid accumulation evoked by alcohol administration. Moreover, PlsEtn more effectively restored endogenous plasmalogen levels than PlsCho, thereby enhancing hepatic antioxidation against "second-hit" reactive oxygen species (ROS) due to the damaged mitochondria and abnormal ethanol metabolism. Taken together, sea cucumber ether-PLs show great potential to become a natural functional food against chronic alcohol-induced hepatic steatosis and lipid metabolic dysregulation.

Wheat embryo globulin protects against acute alcohol-induced liver injury in mice

Wheat Embryo Globulin (WEG) is a high-quality plant-derived protein with anti-inflammatory, antioxidant, and immunity enhancement effects. WEG was prepared and characterized using free amino acid analysis, circular dichroism (CD), and scanning electron microscope (SEM). The liver protection effect of WEG on mice after acute alcohol stimulation was also investigated. Male KM mice were randomly divided into four groups (n = 10). Animals were orally administrated with WEG (60 mg/kg), silymarin (50 mg/kg), and the same volume of saline solution daily for 30 days, before administering an alcohol-intragastric injection. Results displayed that the liver index, the levels of serum total cholesterol (TC), serum triglyceride (TG), liver malondialdehyde (MDA) and the mRNA expression of CYP2E1were significantly decreased in WEG-treated mice compared with the model group. Meanwhile, the levels of serum high-density lipoprotein-cholesterol (HDL-C), hepatic reduced glutathione (GSH), superoxide dismutase (SOD) and the mRNA expression of ADH₂ and ALDH₂ were remarkably increased. Effect of WEG on histopathology of liver tissue confirmed its protective function. Meanwhile, GSH level of ileal was significantly increased, MDA was remarkably decreased in WEG-treated mice, which also indicated that WEG possessed a positive effect on intestinal micro ecological environment health to some extent. In conclusion, WEG is a promising agent for the prevention of acute alcoholic liver injury.