Metabolic effects of dietary supplementation of Lycium barbarum polysaccharides on serum and urine metabolomics in a young healthy male population

A review on the hypoglycemic effect, mechanism and application development of natural dietary polysaccharides

Diabetes mellitus (DM) as one chronic metabolic disease was greatly increased over recent decades. The major agents treating diabetes have noticeable side effects as well as the tolerability problems. The bioactive dietary polysaccharides from abundant natural resources exhibit good hypoglycemic effect with rare adverse effects, which might serve as a candidate to prevent and treat diabetes. However, the correlations between the hypoglycemic mechanism of polysaccharides and their structure were not mentioned in several studies, what's more, most of the current hypoglycemic studies on polysaccharides were based on in vitro and in vivo experiments, and there was a lack of knowledge about the effects in human clinical trials. The aim of this review is to discuss recent literature about the variety of dietary polysaccharides with hypoglycemic activity, as well the mechanism of action and the structure-function relationship are highlighted. Meanwhile, the application of dietary polysaccharides in functional foods and clinical medicine are realized with an in-depth understanding. So as to promote the exploration of dietary polysaccharides in low glycemic healthy foods or clinical medicine to prevent and treat diabetes.

L. barbarum (Lycium barbarum L.) supplementation for lipid profiles in adults: A systematic review and meta-analysis of RCTs

BACKGROUND

Dyslipidemia is a global health concern with an increasing prevalence worldwide. Lycium barbarum (L. barbarum) is widely used as a medicinal and functional food, and evidence suggests that it may be beneficial for lipid management. In this study, we performed a systematic review and meta-analysis of randomized controlled trials investigating the effects of L. barbarum supplementation on lipid profiles in adults.

METHODS

PubMed, China National Knowledge Infrastructure, The Cochrane Library, Web of Science, and Wanfang Database were searched from inception until October 2022. The random-effect model was applied, and the pooled effect sizes were expressed as mean differences (MDs) and 95% confidence intervals (CIs).

RESULTS

The meta-analysis of 5 randomized controlled trials involving 259 subjects indicated that L. barbarum supplementation significantly decreased the triglyceride (TG) concentration (MD: 0.14 mmol/L, 95% CI: 0.08-0.20) and increased the high-density lipoprotein cholesterol concentration (HDL-C) (MD: -0.07 mmol/L, 95% CI: -0.13 to -0.01). However, the reductions in total cholesterol (TC) concentration (MD: 0.11 mmol/L, 95% CI: -0.37 to 0.59) and low-density lipoprotein cholesterol (LDL-C) concentration (MD: 0.21 mmol/L, 95% CI: -0.46 to 0.89) were not statistically significant.

CONCLUSION

The present study showed that L. barbarum supplementation might have some beneficial effects on TG and HDL-C concentrations in adults, and L. barbarum fruit has an even greater effect on TG and HDL-C concentrations. Considering the sensitivity analyses and limitations of the study included, further large-scale studies are needed to confirm these findings.

Effects of Flammulina velutipes polysaccharides on gut microbiota composition and metabolism in vitro fermentation

Flammulina velutipes polysaccharides (FVP) exhibit many biological activities, but the effects on gut microflora and metabolism were still unclear. Here, we explored the composition of FVP, their influence on human gut microflora composition and metabolites. FVP were used to vitro fermentation through human fecal inoculums. In addition, 16S rRNA sequencing were used to assess the effects of FVP on the gut microbiota. The metabolic profiles were investigated using untargeted metabolomics approaches in the LC-MS platform. The results showed that FVP was mainly consisted of glucose, mannose, xylose, fucose and galactose. FVP is shown to increase the relative abundances of Bifidobacteriaceae, as well as Bacteroidaceae and remarkably decrease the numbers of genera Lachnospiraceae coupled with Enterococcaceae. The differential metabolites were identified and mainly involved the metabolism of glycerophospholipid, linoleic acid and synthesis of unsaturated fatty acids. FVP may exhibit biological activity function by regulating gut microflora composition and metabolites.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10068-022-01192-y.

Lycium barbarum Polysaccharide Regulates the Lipid Metabolism and Alters Gut Microbiota in High-Fat Diet Induced Obese Mice

Bioactive compounds provide new insights into the prevention and treatment of obesity. Lycium barbarum polysaccharide (LBP), a biological macromolecule extracted from Goji berry, has displayed potential for regulating lipid metabolism. However, the relationship between gut microbiota regulation and lipid metabolism is not entirely clear. In the present study, 50, 100, and 150 mg/kg LBP were intragastrically administered to C57BL/6J male mice fed with a high-fat diet simultaneously lasting for twelve weeks. The results showed that 150 mg/kg LBP showed significant results and all doses of LBP feeding (50, 100, 150 mg/kg) remarkably decreased both serum and liver total cholesterol (TC) and triglyceride (TG) levels. Treatment of 150 mg/kg LBP seems to be more effective in weight loss, lowering free fatty acid (FFA) levels in serum and liver tissues of mice. LBP feeding increased the gene expression of adiponectin and decreased the gene expression of peroxisome proliferator-activated receptor γ, Cluster of Differentiation 36, acetyl-coA carboxylase, and fatty acid synthase in a dose-dependent manner. In addition, the 16s rDNA Sequencing analysis showed that 150 mg/kg LBP feeding may significantly increase the richness of gut microbiota by up-regulation of the ACE and Chao1 index and altered β-diversity among groups. Treatment of 150 mg/kg LBP feeding significantly regulated the microbial distribution by decreasing the relative abundance of Firmicutes and increasing the relative abundance of Bacteroidetes at the phylum level. Furthermore, the relative abundance of Faecalibaculum, Pantoea, and uncultured_bacterium_f_Muribaculaceae at the genus level was significantly affected by LBP feeding. A significant correlation was observed between body weight, TC, TG, FFA and bile acid and phyla at the genus level. The above results indicate that LBP plays a vital role in preventing obesity by co-regulating lipid metabolism and gut microbiota, but its effects vary with the dose.

Structure and In Vitro Fermentation Characteristics of Polysaccharides Sequentially Extracted from Goji Berry (Lycium barbarum) Leaves

Herein, the chelating agent-soluble fraction (CA), sodium carbonate-soluble fraction (SC), and sodium hydroxide-soluble fraction (SH) were sequentially extracted from the cell wall of goji berry (Lycium barbarum) leaves. Furthermore, SC was purified with Q-Sepharose fast flow resin to obtain the neutral sugar fraction (SC-I) and acid sugar fraction (SC-II). Physicochemical properties of polysaccharides were characterized by high-performance anion-exchange chromatography with pulsed amperometry detection, size exclusion chromatography-multi-angle laser light scattering, Fourier transform infrared spectroscopy, nuclear magnetic resonance, and atomic force microscopy analysis. Additionally, the impact of polysaccharides on modulating human gut microbiota was investigated by in vitro fermentation. A high amount of galacturonic acid (GalA) in CA showed that it was an aggregation of linear homogalacturonan. SC was the main pectic polysaccharide fraction and rich in neutral sugars. SC-I was the neutral sugar fraction with an extremely high molecular weight (2.055 × 10⁶ Da), while SC-II was the acid sugar fraction with a low molecular weight (1.766 × 10⁵ Da). SH seemed like a mixture of pectin and hemicellulose. All the five polysaccharides significantly (P < 0.05) increased the abundance of Bacteroides, Bifidobacteria, and Lactobacilli. To the best of our knowledge, this is the first report on the structure and fermentation characteristics of goji berry leaf polysaccharides, which is meaningful to provide a structural basis for further bioactivity research.

The effect of Lycium barbarum polysaccharide on the glucose and lipid metabolism: A systematic review and meta-analysis

Goji berry has been used in China more than 2,000 years as a traditional medicinal herb and food supplement. Lycium barbarum polysaccharide (LBP), the chief active component in goji berry, has been used to treat hypertension, atherosclerosis and other cardiovascular diseases in Chinese traditional medicine. However, the underlying effects of LBP- mediated activity in blood glucose and lipid metabolism remain poorly understood. The present study aims to apply the meta-analysis to explore the healthy effects of LBP. Eligible studies published up to November 15, 2020, were searched and identified from CNKI, Pubmed, Web of Science, Cocharane library detabases. A total of 315 publications were retrieved and 7 articles were included. The STATA (version 11.0) was applied to process the meta-analysis. The pooled estimate showed that daily consumption of LBP played significant effects on regulating serum triglyceride (TG), fasting blood glucose, and low-density lipoprotein (LDL) and high-density lipoprotein (HDL) concentrations (p < 0.05), while it was effect-free on the total cholesterol (TC). The present study provided a better understanding of current research status and suggested that LBP could play potential role in prevention and therapy for non-communicable chronic diseases, and more scientific evidence are required in the future.Key teaching pointsGoji berry and LBP, its main biologically active ingredient, have a wide range of health promotion effects.The supplement of LBP may played significant effects on regulating serum TG, HDL, LDL and FBG concentrations.Goji may serve as a potential drug to prevent and treat chronic non-communicable diseases in the future.Healthy dietary patterns containing goji berries will be a new choice for consumers in the future.

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

Macroalgae Laminaria japonica (MLJ) has been reported to exhibit various biological activities including improving immunity, anti-aging, anti-tumor, anti-atherosclerosis and anti-diabetic, but the protective mechanisms of MLJ consumption against non-alcoholic fatty liver disease (NAFLD) associated with hyperlipidemia remain poorly understood. This study demonstrated that MLJ consumption prevented high-fat diet (HFD)-induced NAFLD associated with hyperlipidemia in a rat model, and improved hyperlipidemia-related parameters, e.g. serum and hepatic lipid profiles. Moreover, histological analysis showed that MLJ reduced lipid deposition in adipocytes and hepatocytes compared with the HFD group. Such beneficial effects may be associated with the modulation of the intestinal microbiota, especially some key microbial phylotypes involved in lipid metabolism homeostasis. The underlying protective mechanisms of MLJ consumption against HFD-induced NAFLD associated with hyperlipidemia were also studied by ultra-high performance liquid chromatography with quadruple-time of flight mass spectrometry (UPLC-QTOF/MS)-based liver metabolomics coupled with pathway analysis. The metabolic pathway enrichment analysis of the differentially abundant hepatic metabolites indicated that primary bile acid biosynthesis metabolism and cysteine and methionine metabolism were the two main metabolic pathways altered by MLJ consumption when compared with the model group. The analysis of the transcription levels of liver-related genes by RT-qPCR and the expressions of liver-related proteins by immunohistochemistry (IHC) showed that MLJ consumption could regulate the levels of mRNA transcription and protein expression related to hepatic lipid metabolism. In short, this study indicates that MLJ could be developed as functional food supplement for the prevention or treatment of NAFLD associated with hyperlipidemia.

Effects of carboxyl single-walled carbon nanotubes on synthetic wastewater nutrient removal by an algal-bacterial consortium: Regulation and interaction

In this study, the morphology, ultrastructure, nutrient removal, metabolite levels, and interaction of an algal-bacterial consortium exposed to different concentrations of carboxylic single-walled carbon nanotubes (C-SWCNT) were investigated. At a C-SWCNT concentration of 0.05 mg·L^-1, the removal rates of TN, NH₃-N, PO₄^3--P, and COD were 94.7%, 94.8%, 86.4% and 84.3%, respectively. When cells were exposed to 50 mg·L^-1 C-SWCNT, its intracellular levels in individual algae and the algal-bacterial consortium were 23.6 μg·g^-1 and 12.1 μg·g^-1, respectively. C-SWCNT (0.05 mg·L^-1) promoted the metabolism of fatty acids, amino acids, small molecules, and acid in the algal-bacterial consortium. The main response to the interaction of C-SWCNT and the consortium was the change in extracellular carbohydrate levels. C-SWCNT also increased chlorophyll a and glycine levels. These findings reveal new insights into our understanding of the biological responses and interactions between C-SWCNT and algal-bacterial consortium.