Search Results (40)

Background/Objectives: Fructooligosaccharides (FOS) and dried tart cherry (TC) are examples of simple and complex (i.e., within a food matrix) prebiotics that have demonstrated promising osteoprotective activity. In this study, we examined how dietary supplementation with TC or FOS shapes the gut-bone axis to promote bone accrual in young adult mice, and the role of the gut microbiota in mediating these responses. Methods: Studies were performed using 10-wk-old female C57BL/6 mice (n = 10–12/group) fed a control diet or control diet supplemented with 10% TC or FOS for 10 wks alone or in combination with an antibiotic/anti-fungal cocktail to suppress the gut microbiota. The bone phenotype was characterized by dual-energy X-ray absorptiometry, micro-computed tomography and static and dynamic bone histomorphometry. The gut-microbiota was profiled and short chain fatty acids (SCFA) were assessed based on 16S rRNA profiling and gas chromatographic techniques, respectively. Results: FOS and TC enhanced bone structure, with FOS yielding more pronounced benefits across cortical and trabecular compartments. These skeletal improvements with FOS occurred in the absence of systemic changes in bone turnover markers but were accompanied by increases in local bone formation, osteoblast and osteocyte numbers, and bone mineralization in the femur. Both diets altered gut microbiota composition and increased fecal concentrations of the most abundant SCFAs (i.e., acetate, propionate and butyrate), but the response was greater with FOS. Suppression of the gut microbiota and fecal SCFAs with the antibiotic/anti-fungal cocktail inhibited the effects of FOS and TC on cortical bone, but induced unexpected improvements in the trabecular bone. Conclusions: These findings demonstrate differential effects of simple and complex prebiotics on the gut-bone axis in young adult female mice and support a role for SCFA in the cortical bone response, but not in the trabecular bone response with this model of gut microbiota suppression. Full article

Acute myeloid leukemia (AML), the most common acute leukemia among adults, poses significant therapeutic challenges due to diagnostic limitations and the frequent development of treatment resistance. While genomics-based approaches have advanced, DNA aberrations do not always reflect the expression levels of genes and proteins, which are more tightly connected to disease phenotypes. Recently, the role of the gut microbiota in AML has gained increasing attention. AML patients often exhibit gut microbiota dysbiosis, which is linked to disease progression and heightened infection risk. Mounting evidence indicates that gut microbiota metabolism influences hematopoiesis and immune function via the “gut-bone marrow axis,” with microbiota composition and diversity significantly affecting treatment outcomes and prognosis. High-throughput sequencing and metabolomics have identified correlations between gut microbiota composition and its metabolic products with AML clinical characteristics, paving the way for new biomarkers in diagnosis and prognosis. Additionally, treatments such as fecal microbiota transplantation (FMT) show promise in enhancing chemotherapy efficacy and improving patient outcomes. This review highlights recent advances in understanding the role of the gut microbiota in AML and explores new perspectives for its diagnosis and treatment. Full article

As a highly disabling chronic inflammatory disease, rheumatoid arthritis (RA) necessitates novel interventions. Liupao tea is a traditional Chinese dark tea known for its favorable anti-inflammatory properties. This study aims to elucidate the active ingredients and action mechanisms underlying the therapeutic effects of Liupao tea extract (LPTE) in RA. LPTE was preliminarily characterized by LC-MS technology. Network pharmacology and molecular docking predicted anti-RA compounds, targets, and pathways, with key compounds identified using chemical standards. The effect of LPTE on the collagen-induced arthritis mouse model was evaluated through serum biochemical analysis, micro-CT imaging, and histopathological analyses. Integrated serum metabolomics, 16S rRNA sequencing, MetOrigin analysis, SCFA metabolomics, and quantitative real-time PCR elucidated gut–joint axis mechanisms. LPTE effectively attenuated RA symptoms by reducing bone destruction and joint inflammation. Notably, LPTE reshaped gut microbiota by enriching key families such as Monoglobaceae, Eggerthellaceae, and Desulfovibrionaceae, thereby promoting SCFA production. Increased SCFA levels enhanced intestinal barrier integrity and exerted joint-protective and anti-inflammatory effects by upregulating tight junction proteins and activating SCFA receptors. LPTE also modulated arachidonic acid metabolism by affecting key genes such as Alox5, Ptgs2, and Cbr1. These effects collectively reduced the levels of pro-inflammatory cytokines and increased the expression of anti-inflammatory cytokines in joints. Additionally, quercetin, luteolin, ellagic acid, and kaempferol were identified as major anti-RA bioactive compounds in LPTE. Taken together, this study provides preliminary evidence that LPTE mitigates RA by regulating the gut–joint axis mediated via fatty acid metabolism. Full article

Osteoporosis is a systemic bone disorder characterized by decreased bone mass and deteriorated microarchitecture, leading to an increased risk of fractures. Recent studies have revealed that its pathogenesis involves complex biological processes beyond bone remodeling, including oxidative stress, chronic inflammation, cellular senescence, osteoimmunology, gut microbiota alterations, and epigenetic modifications. Oxidative stress disrupts bone homeostasis by promoting excessive free radical production and osteoclast activity. Chronic inflammation and the accumulation of senescent cells impair skeletal repair mechanisms. Advances in osteoimmunology have highlighted the critical role of immune–bone crosstalk in regulating bone resorption and formation. Moreover, the gut–bone axis, mediated by microbial metabolites, influences bone metabolism through immune and endocrine pathways. Epigenetic changes, such as DNA methylation and histone modification, contribute to gene–environment interactions, affecting disease progression. Multi-omics approaches (genomics, proteomics, and metabolomics) systematically identify molecular networks and comorbid links with diabetes/cardiovascular diseases, revealing pathological feedback loops that exacerbate bone loss. In conclusion, osteoporosis pathogenesis extends beyond bone remodeling to encompass systemic inflammation, immunometabolic dysregulation, and gut microbiota–host interactions. Future research should focus on integrating multi-omics biomarkers with targeted therapies to advance precision medicine strategies for osteoporosis prevention and treatment. Full article

While periodontitis is increasingly linked to systemic disorders through the oral–gut axis, the molecular mediators driving gut microbiota dysbiosis and barrier disruption remain elusive. Hepatocyte growth factor (HGF), a novel regulator of inflammatory bone loss in periodontitis, may serve as a critical communicator between oral infection and distal intestinal pathology. This study investigates how HGF overexpression modulates the gut microbial ecosystem and intestinal barrier integrity in a transgenic periodontitis model. In this study, we combined 16S rRNA sequencing of fecal microbiota with comprehensive gut barrier assessments, including systemic markers (D-lactate, LPS, and DAO ELISA), structural integrity (villous morphology), and molecular analysis (ZO-1, occludin, and NOD2 immunohistochemistry), using HGF-overexpressing transgenic (HGF-Tg) mice with periodontitis. The results demonstrated that HGF increased gut permeability in the context of periodontitis, as evidenced by elevated serum levels of D-lactate and LPS compared to wild type (WT) mice. In addition, gut villous morphology disorder was observed in HGF-Tg mice with periodontitis. HGF also diminished the protein level of occludin and upregulated NOD2 expression in mice with periodontitis. Moreover, HGF-Tg mice with periodontitis exhibited significant dysbiosis of gut microbiota, with reduced levels of probiotics (e.g., Faecalibaculum). Notably, HGF also increased the enrichment of the periodontitis-associated pathogens (e.g., Desulfovibrio and Streptococcus) in the gut. Microbial functions, particularly metabolic pathways, were significantly altered by HGF when periodontitis occurred. Some microorganisms like g_Desulfovibrio may play a role in gut barrier disorder in HGF-Tg mice with periodontitis. Overall, our findings position HGF as a novel orchestrator of oral–gut crosstalk, where its overexpression reshapes gut microbial ecology toward a “leaky gut” phenotype to compromise intestinal barrier integrity, further deepening our understanding of the oral–gut axis. Full article

Osteoporosis is a multifactorial bone metabolic disorder characterized by the deterioration of bone mass and microarchitecture, leading to increased fragility and fracture risk. Recent advances have revealed the critical role of the gut microbiota in the pathogenesis of osteoporosis, primarily mediated by metabolite-driven and immune-mediated interactions along the gut–bone axis. Dysbiosis, or microbial imbalance, can influence bone health by modulating host metabolism, immune function, and endocrine responses. While growing evidence suggests that gut microbiota modulation holds therapeutic potential for osteoporosis, the underlying mechanisms remain poorly understood. This review examines the latest findings on the role of prebiotics, probiotics, and natural bioactive substances in modulating the gut microbiota to improve bone health. We discuss how these interventions may restore microbial balance, enhance gut barrier function, and reduce systemic inflammation, thereby influencing bone metabolism. A deeper understanding of the gut–bone axis will pave the way for more targeted, effective, and personalized therapeutic strategies for osteoporosis prevention and treatment. Full article

Background: Lead (Pb), a pervasive environmental toxicant with specific toxicity to bone, has been recognized as a significant etiological factor in the pathogenesis of osteoporosis. While dietary fiber (DF) demonstrates anti-osteoporotic potential, its protective role against Pb-induced bone loss remains unexplored. Methods: This study analyzed the association between dietary fiber, blood lead, and osteoporosis based on the NHANES database, and validated it by constructing a lead exposed mouse model. Micro CT was used to evaluate bone microstructure, ELISA was used to detect bone markers, q-PCR/Western blot was used to measure intestinal tight junction protein, flow cytometry was used to analyze Treg cells in colon/bone tissue, GC-MS was used to detect short chain fatty acids, and 16S rRNA sequencing was used to analyze changes in gut microbiota. The regulatory mechanism of dietary fiber on bone metabolism and intestinal barrier in lead exposed mice was systematically evaluated. Results: Based on NHANES data analysis, it was found that dietary fiber can reduce the risk of osteoporosis in lead exposed populations. Animal experiments have shown that dietary fiber intervention significantly increases bone density, improves bone microstructure and metabolic indicators, repairs intestinal barrier damage caused by lead exposure, and regulates immune balance in lead exposed mice. At the same time, it promotes the generation of short chain fatty acids and the proliferation of beneficial gut microbiota. Conclusions: These findings indicate that DF mitigates Pb-induced osteoporosis through gut barrier restoration, SCFA-mediated immunomodulation, and microbiota-driven Treg cell expansion along the gut–bone axis. Full article

The normal development and growth of bones are critical for poultry health. With the rapid increase in poultry growth rates achieved over the last few decades, juvenile meat-type poultry exhibit a high incidence of leg weakness and lameness. These issues are significant contributors to poor animal welfare and substantial economic losses. Understanding the potential etiology of bone problems in poultry will aid in developing treatments for bone diseases. The gut microbiota represents the largest micro-ecosystem in animals and is closely related to many metabolic disorders, including bone disease. It achieves this by secreting secondary metabolites and coordinating with various tissues and organs through the circulatory system, which leads to the concept of the gut–X axis. Given its importance, modulating gut microbiota to influence the gut–X axis presents new opportunities for understanding and developing innovative therapeutic approaches for poultry bone diseases. In light of the extensive literature on this topic, this review focuses on the effects of gut microbiota on bone density and strength in poultry, both directly and indirectly, through the regulation of the gut–X axis. Our aim is to provide scientific insights into the bone health problems faced by poultry. Full article

Background: High-altitude hypoxia is known to adversely affect bone health, leading to accelerated bone loss and metabolic alterations. Recent studies suggest that factors such as bicarbonate and gut microbiota may play key roles in bone health. Mineral water, rich in bicarbonate, may influence bone health and the gut–bone axis under such conditions. Methods: Mice were exposed to hypoxia and treated with different concentrations of drinking water. Bone-related parameters were assessed using dual-energy X-ray absorptiometry (DXA) and Micro-CT. Bone health was assessed using the measurement of serum biomarkers. Additionally, Untargeted Metabolomics was employed to analyze differential metabolites between groups, while gut microbiota composition was analyzed using 16S rRNA sequencing. Results: BMW consumption increased bone mineral density (BMD) and helped alleviate the damage to the microstructure of bones caused by hypoxia and delayed the progression of osteoporosis. Additionally, BMW was shown to enhance probiotics such as Akkermansia and Dubosiella and regulate the longevity-regulating pathway as well as the PI3K/AKT/mTOR (PAM) signaling pathway. This study also discovered changes in metabolic products due to BMW intervention, predominantly in pathways such as the amino acid, prostaglandin, and purine metabolisms, with correlation analysis further exploring the relationships between gut microbiota and these differential metabolites. Conclusions: Long-term exposure to high-altitude hypoxic conditions affects the structure of gut microbiota and bone metabolism in mice. The consumption of BMW improves the structure of gut microbiota and regulates the metabolic pathways to maintain bone health under high-altitude hypoxia. Full article

Introduction: Osteoarthritis (OA) is the most prevalent form of arthritis and affects over 528 million people worldwide. Degenerative joint disease involves cartilage degradation, subchondral bone remodeling, and synovial inflammation, leading to chronic pain, stiffness, and impaired joint function. Initially regarded as a “wear and tear” condition associated with aging and mechanical stress, OA is now recognized as a multifaceted disease influenced by systemic factors such as metabolic syndrome, obesity, and chronic low-grade inflammation. Recent studies have focused on the gut-joint axis to investigate how the gut microbiome modulates inflammation and pain in OA. Materials and Methods: A systematic review was conducted following the PRISMA guidelines and was registered with PROSPERO (CRD42024556265). This review included studies involving adults with symptomatic OA and analyzed the relationship between the gut microbiome and OA-related pain. Randomized and non-randomized clinical trials, case reports, editorials, and pilot studies were excluded. Searches were performed in PubMed, Cochrane Library, and Web of Science without publication date restrictions, and filtered for “observational studies”. The study selection and data extraction were performed by two independent researchers, and the risk of bias was assessed using appropriate tools. Results: Five observational studies were included in the systematic review, and three were included in the meta-analysis. Two studies reported an association between different tryptophan metabolites and pain levels in patients with OA. Two other studies demonstrated a correlation between lipopolysaccharide levels and pain in OA. A fifth study confirmed the relationship between Streptococcus relative abundance of Streptococcus spp. and knee pain. These results were not supported by a meta-analysis, which found no significant association between the presence of pain in OA and the presence of bacilli of the genus Streptococcus or plasma markers of the tryptophan pathway. Conclusions: Current evidence indicates a potential link between gut microbiome dysbiosis and OA-related pain. However, methodological limitations preclude definitive conclusions. Further research using advanced techniques and larger cohorts is needed to validate and extend these findings and elucidate the underlying mechanisms. Targeted manipulation of the gut microbiome may be a valuable strategy for pain management in OA patients. Full article

Growing scientific evidence suggests a strong interconnection between inflammatory skin diseases and osteoporosis (OP), a systemic condition characterized by decreased bone density and structural fragility. These conditions seem to share common pathophysiological mechanisms, including immune dysregulation, chronic inflammation, and vitamin D deficiency, which play a crucial role in both skin and bone health. Additionally, the roles of gut microbiota (GM) and epigenetic regulation via microRNAs (miRNAs) emerge as key elements influencing the progression of both conditions. This review aims to examine the skin–bone axis, exploring how factors such as vitamin D, GM, and miRNAs interact in a subtle pathophysiological interplay driving skin inflammation and immune-metabolic bone alterations. Recent research suggests that combined therapeutic approaches—including vitamin D supplementation, targeted microbiota interventions, and miRNA-based therapies—could be promising strategies for managing comorbid inflammatory skin diseases and OP. This perspective highlights the need for multidisciplinary approaches in the clinical management of conditions related to the skin-bone axis. Full article

The gut microbiome is essential for regulating host metabolism, defending against pathogens, and shaping the host’s immune system. Mounting evidence highlights that disruption in gut microbial communities significantly impacts cancer development and treatment. Moreover, tumor-associated microbiota, along with its metabolites and toxins, may contribute to cancer progression by promoting epithelial-to-mesenchymal transition, angiogenesis, and metastatic spread to distant organs. Bones, in particular, are common sites for metastasis due to a rich supply of growth and neovascularization factors and extensive blood flow, especially affecting patients with thyroid, prostate, breast, lung, and kidney cancers, where bone metastases severely reduce the quality of life. While the involvement of the gut microbiome in bone metastasis formation is still being explored, proposed mechanisms suggest that intestinal dysbiosis may alter the bone microenvironment via the gut-immune-bone axis, fostering a premetastatic niche and immunosuppressive milieu suitable for cancer cell colonization. Disruption in the delicate balance of bone modeling and remodeling may further create a favorable environment for metastatic growth. This review focuses on the link between beneficial or dysbiotic microbiome composition and bone homeostasis, as well as the role of the microbiome in bone metastasis development. It also provides an overview of clinical trials evaluating the impact of gut microbial community structure on bone parameters across various conditions or health-related issues. Dietary interventions and microbiota modulation via probiotics, prebiotics, and fecal microbiota transplantation help support bone health and might offer promising strategies for addressing bone-related complications in cancer. Full article

The hedgehog (Hh) signalling pathway plays a key role in both embryonic and postnatal development of the intestine and is responsible for gut homeostasis. It regulates stem cell renewal, formation of the villous–crypt axis, differentiation of goblet and Paneth cells, the cell cycle, apoptosis, development of gut innervation, and lipid metabolism. Ligands of the Hh pathway, i.e., Indian hedgehog (Ihh) and Sonic hedgehog (Shh), are expressed by superficial enterocytes but act in the mesenchyme, where they are bound by a Patched receptor localised on myofibroblasts and smooth muscle cells. This activates a cascade leading to the transcription of target genes, including those encoding G1/S-specific cyclin-D2 and -E1, B-cell lymphoma 2, fibroblast growth factor 4, and bone morphogenetic protein 4. The Hh pathway is tightly connected to Wnt signalling. Ihh is the major ligand in the Hh pathway. Its activation inhibits proliferation, while its blocking induces hyperproliferation and triggers a wound-healing response. Thus, Ihh is a negative feedback regulator of cell proliferation. There are data indicating that diet composition may affect the expression of the Hh pathway genes and proteins, which in turn, induces changes in mucosal architecture. This was shown for fat, vitamin A, haem, berberine, and ovotransferrin. The Hh signalling is also affected by the intestinal microbiota, which affects the intestinal barrier integrity. This review highlights the critical importance of the Hh pathway in shaping the intestinal mucosa and summarises the results obtained so far in research on the effect of dietary constituents on the activity of this pathway. Full article

Osteoporosis (OP), which is characterized by a decrease in bone density and increased susceptibility to fractures, is closely linked to the gut microbiota (GM). It is increasingly realized that the GM plays a key role in the maintenance of the functioning of multiple organs, including bone, by producing bioactive metabolites such as short-chain fatty acids (SCFA). Consequently, imbalances in the GM, referred to as dysbiosis, have been identified with a significant reduction in beneficial metabolites, such as decreased SCFA associated with increased chronic inflammatory processes, including the activation of NF-κB at the epigenetic level, which is recognized as the main cause of many chronic diseases, including OP. Furthermore, regular or long-term medications such as antibiotics and many non-antibiotics such as proton pump inhibitors, chemotherapy, and NSAIDs, have been found to contribute to the development of dysbiosis, highlighting an urgent need for new treatment approaches. A promising preventive and adjuvant approach is to combat dysbiosis with natural polyphenols such as resveratrol, which have prebiotic functions and ensure an optimal microenvironment for beneficial GM. Resveratrol offers a range of benefits, including anti-inflammatory, anti-oxidant, analgesic, and prebiotic effects. In particular, the GM has been shown to convert resveratrol, into highly metabolically active molecules with even more potent beneficial properties, supporting a synergistic polyphenol–GM axis. This review addresses the question of how the GM can enhance the effects of resveratrol and how resveratrol, as an epigenetic modulator, can promote the growth and diversity of beneficial GM, thus providing important insights for the prevention and co-treatment of OP. Full article

This study aimed to assess the effects of different dietary vitamin D₃ (VD₃) levels on growth and carcass performance, tibia traits, meat quality, and intestinal morphology of yellow-feathered broilers. One-day-old broilers (n = 1440) were assigned into four treatment groups with six replicates per group, and each replicate contained 60 chicks. Dietary VD₃ significantly improved the growth performance and carcass traits of broilers, and only low-dose VD₃ supplementation decreased the abdominal fat percentage. High-dose VD₃ supplementation improved intestinal morphology in the finisher stage, while the b* value of breast muscle meat color decreased markedly under VD₃ supplementation (p < 0.05). Serum Ca and P levels and the tibia composition correlated positively with dietary VD₃ supplementation at the early growth stage. The weight, length, and ash contents of the tibia increased linearly with increasing dietary VD₃, with maximum values achieved in the high-dose group at all three stages. Intestinal 16S rRNA sequencing and liver transcriptome analysis showed that dietary VD₃ might represent an effective treatment in poultry production by regulating lipid and immune-related metabolism in the gut–liver axis, which promotes the metabolism through the absorption of calcium and phosphorus in the intestine and improves their protective humoral immunity and reduces infection mortality. Dietary VD₃ positively affected the growth—immunity and bone development of broilers during the early stage, suggesting strategies to optimize poultry feeding. Full article