Effect of Bergamot and Laoxianghuang Polysaccharides on Gut Microbiota Derived from Patients with Hyperlipidemia: An Integrative Analysis of Microbiome and Metabolome during In Vitro Fermentation

Xuefu Zhuyu Decoction improves hyperlipidemia through the MAPK/NF-κB and MAPK/PPARα/CPT-1A signaling pathway

Xuefu Zhuyu Decoction (XZD) is widely used in the treatment of cardiovascular diseases. The purpose of this study was to explore the pharmacological effects and molecular mechanisms of XZD in improving hyperlipidemia and to provide a theoretical framework for clinical application. In this study, the signaling pathways regulated by XZD in improving hyperlipidemia were predicted by network pharmacology. Molecular docking was used to verify the affinity between the components in XZD and the target. Furthermore, a hyperlipidemic model in rats was constructed through feeding a high-fat diet. The effect of XZD on hyperlipidemia was verified by histopathological staining, Elisa, and western blot. The results found that the XZD improved dyslipidemia and inflammatory factor disorders, and inhibited liver function damage, pathological damage, and oxidative stress damage in hyperlipidemic rats. The findings from molecular docking and network pharmacology suggested that the mechanism of XZD improving hyperlipidemia may be closely related to the MAPK, NF-κB, and PPAR pathways. This study demonstrated that the XZD inhibited liver lipid metabolism disorder and inflammatory response by regulating the MAPK/NF-κB and MAPK/PPARα/CPT-1A pathway, significantly improved liver histopathological damage and oxidative stress injury, and played a protective role in hyperlipidemic rats.

Laoxianghuang polysaccharide promotes the anti-inflammatory cytokine interleukin-10 in colitis via gut microbial linoleic acid

BACKGROUND

Our previous study found that the polysaccharide from Laoxianghuang (LP), fermented fruit of bergamot (traditional Chinese medicine and food), can alter gut microbiota and regulate short-chain fatty acids (SCFAs) in vitro. Nevertheless, there is a paucity of reports on the impact of LP on gut microbiota in vivo.

PURPOSE

To analyze the structures of LP, investigate the influence of LP on the damaged intestinal barrier in DSS-induced colitis mice, and further explore its potential mechanisms.

METHODS

We analyzed the physicochemical properties of purified LP by HPLC, SEM, and FT-IR spectrum. Then, to assess the effect of LP in DSS-induced colitis mice, we observed the damage to the colon tissue, measured inflammatory cytokines and tight junction protein expression through RT-qPCR as well as immunofluorescent staining, and investigated the influence of LP on altering gut microbiota and metabolites using 16 s rRNA sequencing and HPLC-MS/MS. Ultimately, the impact of linoleic acid on inflammatory cytokines was confirmed by the LPS-induced RAW264.7 cells.

RESULTS

LP, mainly galactoglucan, could inhibit weight loss and colon shortening, decrease levels of tumor necrosis factor-α (TNF-α), increase levels of interleukin-10 (IL-10) and the intestinal acetic acid and butyric acid, and promote the expression of tight junction proteins ZO-1 and Claudin-1. Meanwhile, LP enhanced the abundance of beneficial bacteria including Romboutsia, Eubacterium_coprostanoligenes_group, and Akkermansia, and regulated linoleic acid metabolism to increase the linoleic acid level. In vitro cell experiment proved that linoleic acid could elevate the level of IL-10 and inhibit inflammatory responses.

CONCLUSIONS

Our results suggested that LP effectively alleviated colitis by promoting the anti-inflammatory cytokine interleukin-10 via gut microbiota-mediated linoleic acid metabolism.

Effects of fermented Arctium lappa L. root by Lactobacillus casei on hyperlipidemic mice

Introduction

This study aimed to establish a fermentation system based on Lactobacillus casei (LC) and Arctium lappa L. root (AR) to investigate its effects. The objectives included comparing metabolite profiles pre- and post-fermentation using untargeted metabolomics and evaluating the impact of LC-AR in high-fat diet-induced hyperlipidemic mice.

Methods

Untargeted metabolomics was used to analyze differences in metabolites before and after fermentation. In vitro antioxidant activity, liver injury, lipid levels, pro-inflammatory cytokine levels, and cholesterol-related mRNA expression were assessed. 16S rRNA sequencing was conducted to evaluate changes in gut microbiota composition.

Results

LC-AR exhibited stronger antioxidant activity and higher metabolite levels than AR. It also improved liver injury as well as better regulation of lipid levels, pro-inflammatory cytokine levels, and cholesterol-related mRNA. 16S rRNA analysis revealed that LC-AR decreased the Firmicutes/Bacteroidetes ratio, which correlated negatively with triglycerides, total cholesterol, and low-density lipoprotein cholesterol levels.

Discussion

These findings suggest that LC-AR may serve as a promising functional food and drug raw material for improving hyperlipidemia, particularly through its beneficial effects on gut microbiota and lipid regulation.

Microbial Fermentation Enhances the Effect of Black Tea on Hyperlipidemia by Mediating Bile Acid Metabolism and Remodeling Intestinal Microbes

Black tea (BT), the most consumed tea worldwide, can alleviate hyperlipidemia which is a serious threat to human health. However, the quality of summer BT is poor. It was improved by microbial fermentation in a previous study, but whether it affects hypolipidemic activity is unknown. Therefore, we compared the hypolipidemic activity of BT and microbially fermented black tea (EFT). The results demonstrated that BT inhibited weight gain and improved lipid and total bile acid (TBA) levels, and microbial fermentation reinforced this activity. Mechanistically, both BT and EFT mediate bile acid circulation to relieve hyperlipidemia. In addition, BT and EFT improve dyslipidemia by modifying the gut microbiota. Specifically, the increase in Lactobacillus johnsonii by BT, and the increase in Mucispirillum and Colidextribacter by EFT may also be potential causes for alleviation of hyperlipidemia. In summary, we demonstrated that microbial fermentation strengthened the hypolipidemic activity of BT and increased the added value of BT.

Bergamot polysaccharides relieve DSS-induced ulcerative colitis via regulating the gut microbiota and metabolites

This study aimed to explore the efficacy of polysaccharides from bergamot (BP) in alleviating DSS-induced colitis. Results showed that BP was primarily composed of two components, BP-1 and BP-2, with similar monosaccharide compositions to BP (mainly glucose and xylose) and molecular weights (Mw) of 4.50 × 105 and 2.35 × 105 Da. This study found BP relieved disease symptoms such as weight loss and colon shortening in mice with colitis. Gut microbiota and metabolomics analysis revealed that the BP could also promote the proliferation of beneficial bacteria such as Bifidobacteria, Butyrivibrio, and Blautia, resulting in increased levels of SCFAs and L-phenylalanine, which were associated with phenylalanine, tyrosine, and tryptophan metabolism pathways. Further analysis validated the inflammatory activity of L-phenylalanine. Hence, BP may relieve colitis symptoms by regulating the gut microbiota and metabolism, which reduced inflammation and enhanced the expression of tight junctional proteins (TJ proteins) and mucin in the intestine.

Comparative Study on In Vitro Fermentation Characteristics of the Polysaccharides Extracted from Bergamot and Fermented Bergamot

This study aimed to compare the in vitro fermentation characteristics of polysaccharides from Bergamot and Laoxianghuang (fermented 1, 3, and 5 years from bergamot) using the stable in vitro human gut fermentation model. Results showed that bergamot polysaccharide (BP) and Laoxianghuang polysaccharides (LPs) with different surface topographies were characterized as mannorhamnan (comprising Mannose and Rhamnose) and polygalacturonic acid (comprising Galacturonic acid and Galactose), respectively. The distinct effects on the gut microbiota and metabolome of BP and LPs may be due to their different monosaccharide compositions and surface morphologies. BP decreased harmful Fusobacterium and promoted beneficial Bifidobacterium, which was positively correlated with health-enhancing metabolites such as acetic acid, propionic acid, and pyridoxamine. Lactobacillus, increased by LPs, was positively correlated with 4-Hydroxybenzaldehyde, acetic acid, and butyric acid. Overall, this study elucidated gut microbiota and the metabolome regulatory discrepancies of BP and LPs, potentially contributing to their development as prebiotics in healthy foods.