The protective mechanisms of macroalgae Laminaria japonica consumption against lipid metabolism disorders in high-fat diet-induced hyperlipidemic rats

Saponins from Chenopodium quinoa Willd. husks alleviated high-fat-diet-induced hyperlipidemia via modulating the gut microbiota and multiple metabolic pathways

BACKGROUND

Hyperlipidemia is characterized by abnormally elevated blood lipids. Quinoa saponins (QS) have multiple pharmacological activities, including antitumor, bactericidal and immune-enhancing effects. However, the lipid-lowering effect and mechanisms of QS in vivo have been scarcely reported.

METHODS

The effect of QS against hyperlipidemia induced by high-fat diet in rats was explored based on gut microbiota and serum non-targeted metabolomics.

RESULTS

The study demonstrated that the supplementation of QS could reduce serum lipids, body weight, liver injury and inflammation. 16S rRNA sequencing demonstrated that QS mildly increased alpha-diversity, altered the overall structure of intestinal flora, decreased the relative richness of Firmicutes, the ratio of Firmicutes/Bacteroidetes (P < 0.05) and increased the relative richness of Actinobacteria, Bacteroidetes, Bifidobacterium, Roseburia and Coprococcus (P < 0.05). Simultaneously, metabolomics analysis showed that QS altered serum functional metabolites with respect to bile acid biosynthesis, arachidonic acid metabolism and taurine and hypotaurine metabolism, which were closely related to bile acid metabolism and fatty acid β-oxidation. Furthermore, QS increased protein levels of farnesoid X receptor, peroxisome proliferator-activated receptor α and carnitine palmitoyltransferase 1, which were related to the screened metabolic pathways. Spearman correlation analysis showed that there was a correlation between gut microbiota and differential metabolites.

CONCLUSION

QS could prevent lipid metabolism disorders in hyperlipidemic rats, which may be closely associated with the regulation of the gut microbiota and multiple metabolic pathways. This study may provide new evidence for QS as natural active substances for the prevention of hyperlipidemia. © 2023 Society of Chemical Industry.

Combination of Lycium barbarum L. and Laminaria japonica polysaccharides as a highly efficient prebiotic: Optimal screening and complementary regulation of gut probiotics and their metabolites

The combination of polysaccharides is an effective way to develop prebiotics with stable performance during processing and digestion for human wellness. However, there is little information on optimal screening and complementary regulation of compound polysaccharides. This study aimed to optimally select a combination of Lycium barbarum L. polysaccharide (LBP) and Laminaria japonica polysaccharide (LJP) as a highly efficient prebiotic to regulate the gut probiotics and their metabolites. Two LBPs characterized as rhamnogalacturonan I enriched pectins and two LJPs characterized as fucoidans were obtained by enzyme-assisted acid extraction at moderate and dramatic temperatures and combined in pairs to obtain 4 groups containing 4 proportional combinations. All combinations showed better prebiotic effects than individual LJP. The combination of LBP and LJP extracted at 50 °C at a ratio of 4:1 exhibited the strongest prebiotic effect. The optimal compound polysaccharide achieved superior effect and complementary function via LBP-targeted proliferation of Bifidobacterium, Lactobacillus, and Bacteroides and production of SCFAs and non-SCFA health-associated metabolites, LJP-targeted accumulation of butyrate-producing bacteria and corresponding metabolites, as well as synergistic effect of LJP and LBP at exact proportion. Our study provided theoretical and methodological guidance for optimal screening of compound polysaccharides as new prebiotics.

Healthy regulation of Tibetan Brassica rapa L. polysaccharides on alleviating hyperlipidemia: A rodent study

Hyperlipidemia is a common metabolic disorder, which can lead to obesity, hypertension, diabetes, atherosclerosis and other diseases. Studies have shown that polysaccharides absorbed by the intestinal tract can regulate blood lipids and facilitate the growth of intestinal flora. This article aims to investigate whether Tibetan turnip polysaccharide (TTP) plays a protective role in blood lipid and intestinal health via hepatic and intestinal axes. Here we show that TTP helps to reduce the size of adipocytes and the accumulation of liver fat, playing a dose-dependent effect on ADPN levels, suggesting an effect on lipid metabolism regulation. Meantime, TTP intervention results in the downregulation of intercellular cell adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and serum inflammatory factors (interleukin-6 (IL-6), interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α)), implying that TTP suppresses the progression of inflammation in the body. The expression of key enzymes associated with cholesterol and triglyceride synthesis, such as 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGCR), cholesterol 7α-hydroxylase (CYP7A1), peroxisome proliferator-activated receptors γ (PPARγ), acetyl-CoA carboxylase (ACC), fatty acid synthetase (FAS) and sterol-regulatory element binding proteins-1c (SREBP-1c), can be modulated by TTP. Furthermore, TTP also alleviates the damage to intestinal tissues caused by high-fat diet, restores the integrity of the intestinal barrier, improves the composition and abundance of the intestinal flora and increases the levels of SCFAs. This study provides a theoretical basis for the regulation of body rhythm by functional foods and potential intervention in patients with hyperlipidemia.

Serotonin Transporter (SERT) Expression Modulates the Composition of the Western-Diet-Induced Microbiota in Aged Female Mice

Background. The serotonin transporter (SERT), highly expressed in the gut and brain, is implicated in metabolic processes. A genetic variant of the upstream regulatory region of the SLC6A4 gene encoding SERT, the so-called short (s) allele, in comparison with the long (l) allele, results in the decreased function of this transporter, altered serotonergic regulation, an increased risk of psychiatric pathology and type-2 diabetes and obesity, especially in older women. Aged female mice with the complete (Sert-/-: KO) or partial (Sert+/-: HET) loss of SERT exhibit more pronounced negative effects following their exposure to a Western diet in comparison to wild-type (Sert+/+: WT) animals. Aims. We hypothesized that these effects might be mediated by an altered gut microbiota, which has been shown to influence serotonin metabolism. We performed V4 16S rRNA sequencing of the gut microbiota in 12-month-old WT, KO and HET female mice that were housed on a control or Western diet for three weeks. Results. The relative abundance of 11 genera was increased, and the abundance of 6 genera was decreased in the Western-diet-housed mice compared to the controls. There were correlations between the abundance of Streptococcus and Ruminococcaceae_UCG-014 and the expression of the pro-inflammatory marker Toll-like-Receptor 4 (Tlr4) in the dorsal raphe, as well as the expression of the mitochondrial activity marker perixome-proliferator-activated-receptor-cofactor-1b (Ppargc1b) in the prefrontal cortex. Although there was no significant impact of genotype on the microbiota in animals fed with the Control diet, there were significant interactions between diet and genotype. Following FDR correction, the Western diet increased the relative abundance of Intestinimonas and Atopostipes in the KO animals, which was not observed in the other groups. Erysipelatoclostridium abundance was increased by the Western diet in the WT group but not in HET or KO animals. Conclusions. The enhanced effects of a challenge with a Western diet in SERT-deficient mice include the altered representation of several gut genera, such as Intestinimonas, Atopostipes and Erysipelatoclostridium, which are also implicated in serotonergic and lipid metabolism. The manipulation of these genera may prove useful in individuals with the short SERT allele.

Beneficial effects of seaweed-derived components on metabolic syndrome via gut microbiota modulation

Metabolic syndrome comprises a group of conditions that collectively increase the risk of abdominal obesity, diabetes, atherosclerosis, cardiovascular diseases, and cancer. Gut microbiota is involved in the pathogenesis of metabolic syndrome, and microbial diversity and function are strongly affected by diet. In recent years, epidemiological evidence has shown that the dietary intake of seaweed can prevent metabolic syndrome via gut microbiota modulation. In this review, we summarize the current in vivo studies that have reported the prevention and treatment of metabolic syndrome via seaweed-derived components by regulating the gut microbiota and the production of short-chain fatty acids. Among the surveyed related articles, animal studies revealed that these bioactive components mainly modulate the gut microbiota by reversing the Firmicutes/Bacteroidetes ratio, increasing the relative abundance of beneficial bacteria, such as Bacteroides, Akkermansia, Lactobacillus, or decreasing the abundance of harmful bacteria, such as Lachnospiraceae, Desulfovibrio, Lachnoclostridium. The regulated microbiota is thought to affect host health by improving gut barrier functions, reducing LPS-induced inflammation or oxidative stress, and increasing bile acid production. Furthermore, these compounds increase the production of short-chain fatty acids and influence glucose and lipid metabolism. Thus, the interaction between the gut microbiota and seaweed-derived bioactive components plays a critical regulatory role in human health, and these compounds have the potential to be used for drug development. However, further animal studies and human clinical trials are required to confirm the functional roles and mechanisms of these components in balancing the gut microbiota and managing host health.

In vitro effects of two polysaccharide fractions from Laminaria japonica on gut microbiota and metabolome

To investigate the prebiotic potential of two Laminaria japonica polysaccharide (LJP) fractions with different molecular weights and structures, we conducted in vitro simulated digestion and fermentation with hyperlipidemia-associated human gut microbiota. The results indicated that the LJP fraction with higher molecular weight (HLJP) appeared to have a more complex monosaccharide composition and microstructure than did the LJP fraction with lower molecular weight (LLJP), and both fractions could not be digested by in vitro simulated digestion. After in vitro fermentation, HLJP generated more short-chain fatty acids (SCFAs) and showed stronger ability to regulate core metabolites. Intriguingly, LLJP is better at promoting the proliferation of Akkermansiaceae, while HLJP is more effective in reducing the Firmicutes/Bacteroidetes ratio and increasing the content of Bacteroidaceae and Tannerellaceae. The present study indicates that LLJP and HLJP may have probiotic effects through different approaches and these differences may be related to the molecular weight and structure of the polysaccharides.

Moderating Gut Microbiome/Mitochondrial Axis in Oxazolone Induced Ulcerative Colitis: The Evolving Role of β-Glucan and/or, Aldose Reductase Inhibitor, Fidarestat

A mechanistic understanding of the dynamic interactions between the mitochondria and the gut microbiome is thought to offer innovative explanations for many diseases and thus provide innovative management approaches, especially in GIT-related autoimmune diseases, such as ulcerative colitis (UC). β-Glucans, important components of many nutritious diets, including oats and mushrooms, have been shown to exhibit a variety of biological anti-inflammatory and immune-modulating actions. Our research study sought to provide insight into the function of β-glucan and/or fidarestat in modifying the microbiome/mitochondrial gut axis in the treatment of UC. A total of 50 Wistar albino male rats were grouped into five groups: control, UC, β-Glucan, Fidarestat, and combined treatment groups. All the groups were tested for the presence of free fatty acid receptors 2 and 3 (FFAR-2 and -3) and mitochondrial transcription factor A (TFAM) mRNA gene expressions. The reactive oxygen species (ROS), mitochondrial membrane potential (MMP), and ATP content were found. The trimethylamine N-oxide (TMAO) and short-chain fatty acid (SCFA) levels were also examined. Nuclear factor kappa β (NF-kβ), nuclear factor (erythroid-2)-related factor 2 (Nrf2) DNA binding activity, and peroxisome proliferator-activated receptor gamma co-activator-1 (PGC-1) were identified using the ELISA method. We observed a substantial increase FFAR-2, -3, and TFAM mRNA expression after the therapy. Similar increases were seen in the ATP levels, MMP, SCFA, PGC-1, and Nrf2 DNA binding activity. The levels of ROS, TMAO, and NF-kβ, on the other hand, significantly decreased. Using β-glucan and fidarestat together had unique therapeutic benefits in treating UC by focusing on the microbiota/mitochondrial axis, opening up a new avenue for a potential treatment for such a complex, multidimensional illness.

Intestinal flora: A new target for traditional Chinese medicine to improve lipid metabolism disorders

Lipid metabolism disorders (LMD) can cause a series of metabolic diseases, including hyperlipidemia, obesity, non-alcoholic fatty liver disease (NAFLD) and atherosclerosis (AS). Its development is caused by more pathogenic factors, among which intestinal flora dysbiosis is considered to be an important pathogenic mechanism of LMD. In recent years, the research on intestinal flora has made great progress, opening up new perspectives on the occurrence and therapeutic effects of diseases. With its complex composition and wide range of targets, traditional Chinese medicine (TCM) is widely used to prevent and treat LMD. This review takes intestinal flora as a target, elaborates on the scientific connotation of TCM in the treatment of LMD, updates the therapeutic thinking of LMD, and provides a reference for clinical diagnosis and treatment.

Interventions for non-alcoholic liver disease: a gut microbial metabolites perspective

Over the past two decades, non-alcoholic fatty liver disease (NAFLD) has become a leading burden of hepatocellular carcinoma and liver transplantation. Although the exact pathogenesis of NAFLD has not been fully elucidated, recent hypotheses placed more emphasis on the crucial role of the gut microbiome and its derivatives. Reportedly, microbial metabolites such as short-chain fatty acids, amino acid metabolites (indole and its derivatives), bile acids (BAs), trimethylamine N-oxide (TMAO), and endogenous ethanol exhibit sophisticated bioactive properties. These molecules regulate host lipid, glucose, and BAs metabolic homeostasis via modulating nutrient absorption, energy expenditure, inflammation, and the neuroendocrine axis. Consequently, a broad range of research has studied the therapeutic effects of microbiota-derived metabolites. In this review, we explore the interaction of microbial products and NAFLD. We also discuss the regulatory role of existing NAFLD therapies on metabolite levels and investigate the potential of targeting those metabolites to relieve NAFLD.

Global seaweed farming and processing in the past 20 years

Seaweed has emerged as one of the most promising resources due to its remarkable adaptability, short development period, and resource sustainability. It is an effective breakthrough to alleviate future resource crises. Algal resources have reached a high stage of growth in the past years due to the increased output and demand for seaweed worldwide. Several aspects global seaweed farming production and processing over the last 20 years are reviewed, such as the latest situation and approaches of seaweed farming. Research progress and production trend of various seaweed application are discussed. Besides, the challenges faced by seaweed farming and processing are also analyzed, and the related countermeasures are proposed, which can provide advice for seaweed farming and processing. The primary products, extraction and application, or waste utilization of seaweed would bring greater benefits with the continuous development and improvement of applications in various fields.

Graphical Abstract

The Effect of Laminaria japonica on Metabolic Syndrome: A Systematic Review of Its Efficacy and Mechanism of Action

Metabolic syndrome (MetS) is a medical condition characterized by abdominal obesity, insulin resistance, high blood pressure, and hyperlipidemia. An increase in the incidence of MetS provokes an escalation in health care costs and a downturn in quality of life. However, there is currently no cure for MetS, and the absence of immediate treatment for MetS has prompted the development of novel therapies. In accordance with recent studies, the brown seaweed Laminaria japonica (LJP) has anti-inflammatory and antioxidant properties, and so forth. LJP contains bioactive compounds used as food globally, and it has been used as a medicine in East Asian countries. We conducted a systematic review to examine whether LJP could potentially be a useful therapeutic drug for MetS. The following databases were searched from initiation to September 2021: PubMed, Web of Science, EMBASE, and Cochrane Central Register of Controlled Trials Library. Clinical trials and in vivo studies evaluating the effects of LJP on MetS were included. LJP reduces the oxidative stress-related lipid mechanisms, inflammatory cytokines and macrophage-related chemokines, muscle cell proliferation, and migration. Bioactive-glucosidase inhibitors reduce diabetic complications, a therapeutic target in obesity and type 2 diabetes. In obesity, LJP increases AMP-activated protein kinase and decreases acetyl-CoA carboxylase. Based on our findings, we suggest that LJP could treat MetS, as it has pharmacological effects on MetS.

Sulfated Fucogalactan From Laminaria Japonica Ameliorates β-Cell Failure by Attenuating Mitochondrial Dysfunction via SIRT1-PGC1-α Signaling Pathway Activation

As mitochondrial metabolism is a major determinant of β-cell insulin secretion, mitochondrial dysfunction underlies β-cell failure and type 2 diabetes mellitus progression. An algal polysaccharide of Laminaria japonica, sulfated fucogalactan (SFG) displays various pharmacological effects in a variety of conditions, including metabolic disease. We investigated the protective effects of SFG against hydrogen peroxide (H2O2)-induced β-cell failure in MIN6 cells and islets. SFG significantly promoted the H2O2-inhibited proliferation in the cells and ameliorated their senescence, and potentiated β-cell function by regulating β-cell identity and the insulin exocytosis-related genes and proteins in H2O2-induced β-cells. SFG also attenuated mitochondrial dysfunction, including alterations in ATP content, mitochondrial respiratory chain genes and proteins expression, and reactive oxygen species and superoxide dismutase levels. Furthermore, SFG resulted in SIRT1-PGC1-α pathway activation and upregulated the downstream Nrf2 and Tfam. Taken together, the results show that SFG attenuates H2O2-induced β-cell failure by improving mitochondrial function via SIRT1-PGC1-α signaling pathway activation. Therefore, SFG is implicated as a potential agent for treating pancreatic β-cell failure.

Dietary Macroalgae Saccharina japonica Ameliorates Liver Injury Induced by a High-Carbohydrate Diet in Swamp Eel (Monopterus albus)

A high-carbohydrate diet lowers the rearing cost and decreases the ammonia emission into the environment, whereas it can induce liver injury, which can reduce harvest yields and generate economic losses in reared fish species. Macroalgae Saccharina japonica (SJ) has been reported to improve anti-diabetic, but the protective mechanism of dietary SJ against liver injury in fish fed a high-carbohydrate diet has not been studied. Therefore, a 56-day nutritional trial was designed for swamp eel Monopterus albus, which was fed with the normal diet [20% carbohydrate, normal carbohydrate (NC)], a high carbohydrate diet (32% carbohydrate, HC), and a HC diet supplemented with 2.5% SJ (HC-S). The HC diet promoted growth and lowered feed coefficient (FC), whereas it increased hepatosomatic index (HSI) when compared with the NC diet in this study. However, SJ supplementation increased iodine contents in muscle, reduced HSI, and improved liver injury, such as the decrease of glucose (GLU), total bile acid (TBA), and alanine aminotransferase (ALT) in serum, and glycogen and TBA in the liver. Consistently, histological analysis showed that SJ reduced the area of lipid droplet, glycogen, and collagen fiber in the liver (p < 0.05). Thoroughly, the underlying protective mechanisms of SJ supplementation against HC-induced liver injury were studied by liver transcriptome sequencing coupled with pathway analysis. The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis of the differentially expressed genes (DEGs), such as the acetyl-coenzyme A synthetase (acss1), alcohol dehydrogenase (adh), interferon-induced protein with tetratricopeptide repeats 1 (ifit1), aldo-keto reductase family 1 member D1 (akr1d1), cholesterol 7-alpha-monooxygenase (cyp7a1), and UDP-glucuronosyltransferase (ugt), indicated that the pathway of glycolysis/gluconeogenesis was the main metabolic pathway altered in the HC group compared with the NC group. Meanwhile, hepatitis C, primary BA biosynthesis, and drug metabolism-cytochrome P450 were the three main metabolic pathways altered by SJ supplementation when compared with the HC group. Moreover, the BA-targeted metabolomic analysis of the serum BA found that SJ supplementation decreased the contents of taurohyocholic acid (THCA), taurochenodeoxycholic acid (TCDCA), taurolithocholic acid (TLCA), nordeoxycholic acid (NorDCA), and increased the contents of ursocholic acid (UCA), allocholic acid (ACA), and chenodeoxycholic acid (CDCA). In particular, the higher contents of UCA, ACA, and CDCA regulated by SJ were associated with lower liver injury. Overall, these results indicate that the 2.5% supplementation of SJ can be recommended as a functional feed additive for the alleviation of liver injury in swamp eel-fed high-carbohydrate diets.

Ganoderic acid A from Ganoderma lucidum protects against alcoholic liver injury through ameliorating the lipid metabolism and modulating the intestinal microbial composition

Alcoholic liver injury is mainly caused by long-term excessive alcohol consumption and has become a global public threat to human health. It is well known that Ganoderma lucidum has excellent beneficial effects on liver function and lipid metabolism. The object of this study was to investigate the hepatoprotective effects of ganoderic acid A (GAA, one of the main triterpenoids in G. lucidum) against alcohol-induced liver injury and reveal the underlying mechanisms of its protective effects. The results showed that oral administration of GAA significantly inhibited the abnormal elevation of the liver index, serum total triglyceride (TG), cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in mice exposed to alcohol intake, and also significantly protected the liver against alcohol-induced excessive lipid accumulation and pathological changes. Besides, alcohol-induced oxidative stress in the liver was significantly ameliorated by the dietary intervention of GAA through decreasing the hepatic levels of lactate dehydrogenase (LDH) and malondialdehyde (MDA), and increasing hepatic activities of catalase (CAT), superoxide dismutase (SOD), alcohol dehydrogenase (ADH), aldehyde dehydrogenase (ALDH), and hepatic levels of glutathione (GSH). In addition, GAA intervention evidently ameliorated intestinal microbial disorder by markedly increasing the abundance of Muribaculaceae, Prevotellaceae, Jeotgalicoccus, Bilophila, Family_XIII_UCG_001, Aerococcus, Ruminococcaceae_UCG_005, Harryflintia, Christensenellaceae, Rumonpcpccaceae, Prevotelaceae_UCG_001, Clostridiales_vadinBB60_group, Parasutterella and Bifidobacterium, but decreasing the proportion of Lactobacillus, Burkholderia_Caballeroria_Paraburkholderia, Escherichia_Shigella and Erysipelatoclostridium. Furthermore, liver metabolomics based on UPLC-QTOF/MS demonstrated that oral administration of GAA had a significant regulatory effect on the composition of liver metabolites in mice exposed to alcohol intake, especially the levels of the biomarkers involved in the metabolic pathways of riboflavin metabolism, glycine, serine and threonine metabolism, pyruvate metabolism, glycolysis/gluconeogenesis, biosynthesis of unsaturated fatty acids, synthesis and degradation of ketone bodies, fructose and mannose metabolism. Moreover, dietary supplementation of GAA significantly regulated the hepatic mRNA levels of lipid metabolism and inflammatory response related genes. Conclusively, these findings demonstrate that GAA has beneficial effects on alleviating alcohol-induced liver injury and is expected to become a new functional food ingredient for the prevention of alcoholic liver injury.

Revealing the Mechanism of Huazhi Rougan Granule in the Treatment of Nonalcoholic Fatty Liver Through Intestinal Flora Based on 16S rRNA, Metagenomic Sequencing and Network Pharmacology

Background: The incidence of Nonalcoholic Fatty Liver (NAFL) is increasing year by year, growing evidence suggests that the intestinal flora plays a causative role in NAFL. Huazhi Rougan Granule (HRG) is commonly used in the clinical treatment of NAFL. It is reported that it can reduce lipids and protect the liver, but no research has confirmed whether the drug's effect is related to the intestinal flora. Therefore, we investigated whether the effect of HRG is related to the regulation of intestinal flora to further explore the mechanism of HRG in the treatment of NAFL through intestinal flora. Methods: In this study, C57BL/6J mice were fed a high-fat diet for 8 weeks, and the high-fat diet plus HRG or polyene phosphatidylcholine capsules were each administered by gavage for 4 weeks. High-throughput sequencing, network pharmacology, and molecular docking were used to explore the mechanism of HRG in the treatment of NAFL through intestinal flora. Results: HRG treatment can reduce body weight gain, lipid accumulation in liver and lipogenesis and reduce serum biochemical indexes in high-fat-fed mice. Analysis of intestinal flora showed that HRG changed the composition of intestinal flora, which was characterized by a decrease in the Firmicutes/Bacteroidetes ratio. Moreover, the species distribution was significantly correlated with AKP, HDL-C, and TG. Metagenetic analysis showed that HRG altered the functional composition and functional diversity of microorganisms, which was mainly characterized by an increase in the abundance of metabolic pathways. The network pharmacology results show that the mechanism of HRG in the treatment of NAFL through intestinal flora is mainly reflected in the biological process of gene function and related to infectious diseases, immune systems, and signal transduction pathways, such as cytokine-cytokine receptor interaction, Chagas disease, IL-17 signaling pathway and other signaling pathways. Conclusion: These results strongly suggest that HRG may alleviate NAFL by preventing IFD.

A designed self-microemulsion delivery system for dihydromyricetin and its dietary intervention effect on high-fat-diet fed mice

The present study aims to design a self-microemulsion delivery system (d-α-tocopheryl polyethylene glycol 1000 succinate - quillaja saponin) to enhance the absorptivity of dihydromyricetin (DMY-S), and to investigate its dietary intervention effect on high-fat-diet (HFD) fed mice. We find DMY-S can inhibit the increase of body weight and fat mass, preventing non-alcoholic fatty liver disease. Compared to the model group, the abundance of mice intestinal flora is mainly changed in certain bacterial genera of Firmicutes and Bacteroides, including norank_f_Muribaculaceae and Blautia. The result of metabolism analysis indicated that the expression levels of cincassiol B, creatine, pantothenic acid and aminobutyric acid in the liver tissues of mice treated with DMY-S showed a down-regulation. The DMY-S prevented hyperlipidemia in HFD mice mainly by affecting different pathways including glycerophospholipid metabolism, sphingolipid metabolism and pantothenate and CoA biosynthesis.

Seaweed Exhibits Therapeutic Properties against Chronic Diseases: An Overview

Seaweeds or marine macroalgae are known for producing potentially bioactive substances that exhibit a wide range of nutritional, therapeutic, and nutraceutical properties. These compounds can be applied to treat chronic diseases, such as cancer, cardiovascular disease, osteoporosis, neurodegenerative diseases, and diabetes mellitus. Several studies have shown that consumption of seaweeds in Asian countries, such as Japan and Korea, has been correlated with a lower incidence of chronic diseases. In this study, we conducted a review of published papers on seaweed consumption and chronic diseases. We used the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) method for this study. We identified and screened research articles published between 2000 and 2021. We used PubMed and ScienceDirect databases and identified 107 articles. This systematic review discusses the potential use of bioactive compounds of seaweed to treat chronic diseases and identifies gaps where further research in this field is needed. In this review, the therapeutic and nutraceutical properties of seaweed for the treatment of chronic diseases such as neurodegenerative diseases, obesity, diabetes, cancer, liver disease, cardiovascular disease, osteoporosis, and arthritis were discussed. We concluded that further study on the identification of bioactive compounds of seaweed, and further study at a clinical level, are needed.

Intestinal microbiomics and liver metabolomics insights into the preventive effects of chromium (III)-enriched yeast on hyperlipidemia and hyperglycemia induced by high-fat and high-fructose diet

In recent years, organic chromium (III) supplements have received increasing attentions for their low toxicity, high bioavailability and wide range of health-promoting benefits. This study aimed to investigate the preventive effects of chromium (III)-enriched yeast (YCr) on high-fat and high-fructose diet (HFHFD)-induced hyperlipidemia and hyperglycemia in mice, and further clarify its mechanism of action from the perspective of intestinal microbiomics and liver metabolomics. The results indicated that oral administration of YCr remarkably inhibited the aberrant elevations of body weight, blood glucose and lipid levels, hepatic cholesterol (TC) and triglyceride (TG) levels caused by HFHFD. Liver histological examination showed that oral YCr intervention inhibited HFHFD induced liver lipid accumulation. Besides, 16S rDNA amplicon sequencing showed that YCr intervention was beneficial to ameliorating intestinal microbiota dysbiosis by altering the proportion of some intestinal microbial phylotypes. Correlation-based network analysis indicated that the key intestinal microbial phylotypes intervened by YCr were closely related to some biochemical parameters associated with glucose and lipid metabolism. Liver metabolomics analysis revealed that dietary YCr intervention significantly regulated the levels of some biomarkers involved in purine metabolism, glycerophospholipid metabolism, citrate cycle, pyrimidine metabolism, glycerophospholipid metabolism, phenylalanine, tyrosine and tryptophan biosynthesis, and so on. Moreover, dietary YCr intervention regulated the mRNA levels of key genes associated with glucose, cholesterol, fatty acids and bile acids metabolism in liver. These findings suggest that dietary YCr intervention has beneficial effects on glucose and lipid metabolism by regulating intestinal microbiota and liver metabolic pathway, and thus can be served as a functional component to prevent hyperlipidemia and hyperglycemia.

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Chromium-enriched yeast enhances glucose tolerance and liver glycogen synthesis.

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Chromium-enriched yeast ameliorates the disturbance of intestinal microbiota.

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Explore the hepatoprotective effect of chromium-enriched yeast based on metabolomics.

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Chromium-enriched yeast alleviates lipid metabolism through “gut-liver” axis.

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Chromium-enriched yeast intervention affects hepatic gene transcription levels.

Soluble Polysaccharide Derived from Laminaria japonica Attenuates Obesity-Related Nonalcoholic Fatty Liver Disease Associated with Gut Microbiota Regulation

In this study, the effects of a polysaccharide derived from Laminaria japonica (LJP) on obesity were investigated in mice fed a high-fat diet (HFD). LJP significantly attenuated obesity-related features, lowering serum triglycerides, glucose, total cholesterol and low-density lipoprotein cholesterol levels. HFD-induced liver steatosis and hepatocellular ballooning were significantly attenuated by LJP. Additionally, LJP was found to significantly modulate hepatic gene expressions of AMPK and HMGCR, which are key regulators of lipid and cholesterol metabolism. We further found that LJP ameliorated HFD-induced gut microbiota (GM) dysbiosis by significantly reducing the obesity-related Firmicutes to Bacteroidetes ratio, meanwhile promoting the growth of Verrucomicrobia at the phylum level. At the genus level, propionate-producing bacteria Bacteroides and Akkermansia were elevated by LJP, which might explain the result that LJP elevated fecal propionate concentration. Taken together, these findings suggest that dietary intake of LJP modulates hepatic energy homeostasis to alleviate obesity-related nonalcoholic fatty liver disease associated with GM regulation.

The beneficial effects of Lactobacillus brevis FZU0713-fermented Laminaria japonica on lipid metabolism and intestinal microbiota in hyperlipidemic rats fed with a high-fat diet

This study aimed to investigate the beneficial effects of the oral administration of Lactobacillus brevis FZU0713-fermented Laminaria japonica (FLJ) on lipid metabolism and intestinal microbiota in hyperlipidemic rats fed with a high-fat diet (HFD). The results demonstrated that the oral administration of FLJ significantly inhibited obesity and improved the serum and hepatic biochemical parameters in HFD-fed rats. Histopathological results also indicated that FLJ intervention could significantly reduce the accumulation of lipid droplets in the liver induced by HFD feeding. Furthermore, FLJ intervention up-regulated the fecal short-chain fatty acid (SCFA) levels (mainly acetate, propionate and isobutyrate) in HFD-fed rats. Intestinal microbiota profiling by 16S rRNA gene sequencing revealed that FLJ intervention increased the relative abundance of Akkermansia, Collinsella, Ruminococcaceae_UCG-013, Defluviitaleaceae_UCG-011, Intestinimonas, Actinomyces and Tyzzerella, but decreased the abundance of Flavonifractor, Collinsella, Sporosarcina and Lacticigenium. Based on Spearman's correlation, the fecal levels of TC, TG, acetic acid and butyric acid were positively correlated with the relative abundance of Akkermansia and Ruminococcaceae_NK4A214, but negatively correlated with the relative amount of Flavonifractor and Collinsella. The metabolic function of intestinal microbiota predicted by PICRUSt analysis of 16S rRNA gene sequences demonstrated that primary and secondary bile acid biosyntheses, fatty acid biosynthesis, taurine and hypotaurine metabolism, arachidonic acid metabolism, glycolysis/gluconeogenesis, etc. were significantly down-regulated after 8 weeks of FLJ intervention. Additionally, FLJ intervention significantly regulated the hepatic mRNA levels (including BSEP, CYP7A1, LDLR, HMGCR, CD36 and SREBP1-C) involved in lipid metabolism and bile acid homeostasis. In conclusion, these findings support the possibility that Laminaria japonica fermented with probiotic Lactobacillus has the potential to reduce the disturbance of lipid metabolism by regulating intestinal microflora and liver gene expression profiles, so it can be employed as a potential functional food to prevent hyperlipidemia.

Application of metabolomics for revealing the interventional effects of functional foods on metabolic diseases

Metabolomics is an important branch of systems biology, which can detect changes in the body's metabolism before and after the intervention of functional foods, identify effective metabolites, and predict the interventional effects and the mechanism. This review summarizes the latest research outcomes regarding interventional effects of functional foods on metabolic diseases via metabolomics analysis. Since metabolomics approaches are powerful strategies for revealing the changes in bioactive compounds of functional foods during processing and storage, we also discussed the effects of these parameters on functional food metabolites using metabolomics approaches. To date, a number of endogenous metabolites related to the metabolic diseases after functional foods intervention have been discovered. Unfortunately, the mechanisms of metabolic disease-related molecules are still unclear and require further studies. The combination of metabolomics with other omics technologies could further promote its ability to fully understand the precise biological processes of functional food intervention on metabolic diseases.

Associations between TUBB-WWOX SNPs, their haplotypes, gene-gene, and gene-environment interactions and dyslipidemia

In this study, we investigated associations between single nucleotide polymorphisms (SNPs) in the tubulin beta class I (TUBB) and WW domain-containing oxidoreductase (WWOX) genes, gene-gene interactions, and gene-environment interactions and dyslipidemia in the Chinese Maonan ethnic group. Four SNPs (rs3132584, rs3130685, rs2222896, and rs2548861) were genotyped in unrelated subjects with normal lipid levels (864) or dyslipidemia (1129). While 5.0% of Maonan subjects carried the rs3132584TT genotype, none of the Chinese Han in Beijing subjects did. Allele and genotype frequencies differed between the normal and dyslipidemia groups for three SNPs (rs3132584, rs3130685, and rs2222896). rs2222896G allele carriers in the normal group had higher low-density lipoprotein cholesterol and lower high-density lipoprotein cholesterol levels. The rs3132584GG, rs3130685CC+TT, and rs2222896GG genotypes as well as the rs2222896G-rs2548861G and rs2222896G-rs2548861T haplotypes were associated with an elevated risk of dyslipidemia; the rs2222896A-rs2548861T and rs2222896A-rs2548861G haplotypes were associated with a reduced risk of dyslipidemia. Among the thirteen TUBB-WWOX interaction types identified, rs3132584T-rs3130685T-rs2222896G-rs2548861T increased the risk of dyslipidemia 1.371-fold. Fourteen two- to four-locus optimal interactive models for SNP-SNP, haplotype-haplotype, gene-gene, and gene-environment interactions exhibited synergistic or contrasting effects on dyslipidemia. Finally, the interaction between rs3132584 and rs2222896 increased the risk of dyslipidemia 2.548-fold and predicted hypertension.