High-fat diets (HFD) disrupt lipid homeostasis, posing major public health risks. This study investigated the effect of ACA-DK, an insoluble dietary fiber derived from Antrodia camphorata, on HFD-induced dyslipidemia. We demonstrate that ACA-DK effectively alleviates HFD-induced dyslipidemia in mice, counteracting metabolic disorders, aberrant blood lipids, and weight gain. Mechanistically, ACA-DK modulates triglycerides, phosphatidylcholine, and phosphatidylethanolamine via glycerophospholipid/choline/linoleic acid metabolism pathways, while rectifying gut dysbiosis through selective reduction of pro-inflammatory genera (Oscillibacter, Ruminiclostridium, Negativibacillus, Ruminococcaceae and Helicobacter). Integrated analysis identifies Ruminococcaceae and Helicobacter as key mediators of ACA-DK’s lipid-regulatory effects, establishing microbiota-directed therapy as a strategy against dyslipidemia. We thus propose ACA-DK as a microbiota-directed dual-target therapy, simultaneously reprogramming host lipid metabolism and gut ecology to combat diet-induced metabolic diseases. These findings suggest that ACA-DK is a promising prebiotic dietary fiber for ameliorating HFD-induced lipid metabolic disorders, with potential for future development into functional foods or supplements.

Yeast and lactic acid bacteria (LAB) are widely used for the production of fermented foods and play a pivotal role in the production of fermented foods, and their modes of action in the fermentation system directly determines the quality of the final product. Studying the interaction mode between yeast and LAB in the fermentation system is helpful to reveal the relationship between microorganisms and food functions, and is of great significance to the positive regulation of the fermentation process. The interaction modes between yeast and LAB during food fermentation are reviewed herein, including synergy/antagonism, nutrient and metabolite exchange, quorum sensing, and biofilm coating. Besides, we discuss the positive role of yeast-LAB interaction in improving the flavor and texture of fermented foods, shortening the fermentation cycle, and enhancing the probiotic characteristics of the product. Finally, future prospects for the application of yeast and LAB as a mixed starter culture for enhancing fermentation are discussed.

Previous studies have shown that Lactobacillus plantarum AR495 has good anti-inflammatory and antiosteoporosis effects. In order to further explore the effect and mechanism of AR495 in alleviating osteoporosis (OA), a rat model of OA was established to investigate the effects of AR495 on OA markers, inflammatory factor levels and oxidative stress injury in OA rats and to verify the recovery of cartilage matrix and bone by pathological staining of joints and microtomography (micro-CT) imaging. The results showed that AR495 could significantly alleviate excessive body mass gain caused by decreased physical activity in OA rats (P < 0.05). Pathological analysis showed that AR495 could significantly reduce the level of tumor necrosis factor-α (TNF-α) in the joint tissue of OA rats, inhibit the production of matrix metalloproteinase-13 (MMP-13) and the production of C-telopeptide of type Ⅱ collagen (CTX-Ⅱ) as a degradation product of cartilage matrix, thereby alleviating the degradation of articular cartilage matrix in rats. Micro-CT imaging showed that AR495 could significantly alleviate bone loss in the joint of OA rats and effectively protect the integrity of cartilage and synovium of rats. In addition, AR495 could significantly increase the activity of superoxide dismutase (SOD) and reduce the concentration of malondialdehyde (MDA) in peripheral blood (P < 0.05). Quantitative real-time polymerase chain reaction (qPCR) analysis showed that AR495 could stimulate the expression of the mucin-2 (MUC-2) and occludin-1 genes in intestinal goblet cells and repair the intestinal barrier function. It can be seen that AR495 can alleviate OA inflammation level and create a beneficial internal environment for chondrocytes to exert their functions and produce collagen matrix, thereby alleviating and restoring joint injury and improving OA symptoms.

A dual-luciferase reporter gene system to rapidly screen for probiotics with anti-inflammatory activity was constructed in this study. The conditions for the transfection of dual-luciferase plasmids containing nuclear factor-kappa B (NF-κB) response elements into 293T cells and the concentration of lipopolysaccharide (LPS) as an inducer were optimized. The anti-inflammatory activity of 86 selected strains was comparatively evaluated using this system and macrophage RAW264.7 cells. The results showed that the optimal transfection conditions were determined as 50:1, 1:1, 24 h and 100 ng/mL for pNF-κB-luc to pRL-TK plasmid ratio, plasmid to transfection reagent concentration ratio, transfection time, and LPS concentration, respectively. The dual-luciferase reporter system was reliable (Z’= 0.6632) and stable (R² = 0.74699), and its results were consisted with those obtained using macrophage RAW264.7 cells. Finally, three strains with excellent anti-inflammatory effect, Lactiplantibacillus plantarum X30, Limosilactobacillus fermentum X58 and Weissella confusa X83, were obtained by this method. Each strain effectively inhibited the activation of the NF-κB pathway, significantly reduced the expression of pro-inflammatory factors such as interleukin (IL)-1β, tumor necrosis factor-α, and NF-κB p65, and increased the expression of IL-10. This system provides a new idea for targeted screening for probiotics with anti-inflammatory activity.

Probiotics have great potential in regulating intestinal pain. In this study, the effects of Lactobacillus plantarum AR495 on the visceral sensitivity and gut microbiota of irritable bowel syndrome (IBS) rats were studied. The results showed that tryptase released after mast cell activation and degranulation plays a key role in visceral pain, and L. plantarum AR495 reduced the stimulation of colonic mast cells and the expression of protease-activated receptor 2 (PAR2) and TRPV1 in dorsal root ganglia. Research further showed that supplementation with L. plantarum AR495 increased the level of short-chain fatty acids (SCFAs) and enhanced the barrier function of the colo n. In addition, the microbiota analysis of the colon indicated that L. plantarum AR495 promoted the proliferation of Bifidobacterium and inhibited the proliferation of Lachnospiraceae, which alleviated the imbalance of the intestinal microbiota caused by IBS to a certain extent. In total, L. plantarum AR495 might reduce visceral sensitivity through the Mast cell-PAR2-TRPV1 signaling pathway by maintaining the homeostasis of the intestinal barrier.