Macrophage-mediated myelin recycling fuels brain cancer malignancy.

Tumors growing in metabolically challenged environments, such as glioblastoma in the brain, are particularly reliant on crosstalk with their tumor microenvironment (TME) to satisfy their high energetic needs. To study the intricacies of this metabolic interplay, we interrogated the heterogeneity of the glioblastoma TME using single-cell and multi-omics analyses and identified metabolically rewired tumor-associated macrophage (TAM) subpopulations with pro-tumorigenic properties. These TAM subsets, termed lipid-laden macrophages (LLMs) to reflect their cholesterol accumulation, are epigenetically rewired, display immunosuppressive features, and are enriched in the aggressive mesenchymal glioblastoma subtype. Engulfment of cholesterol-rich myelin debris endows subsets of TAMs to acquire an LLM phenotype. Subsequently, LLMs directly transfer myelin-derived lipids to cancer cells in an LXR/Abca1-dependent manner, thereby fueling the heightened metabolic demands of mesenchymal glioblastoma. Our work provides an in-depth understanding of the immune-metabolic interplay during glioblastoma progression, thereby laying a framework to unveil targetable metabolic vulnerabilities in glioblastoma.

GLA-modified RNA treatment lowers GB3 levels in iPSC-derived cardiomyocytes from Fabry-affected individuals.

Recent studies in non-human model systems have shown therapeutic potential of nucleoside-modified messenger RNA (modRNA) treatments for lysosomal storage diseases. Here, we assessed the efficacy of a modRNA treatment to restore the expression of the galactosidase alpha (GLA), which codes for α-Galactosidase A (α-GAL) enzyme, in a human cardiac model generated from induced pluripotent stem cells (iPSCs) derived from two individuals with Fabry disease. Consistent with the clinical phenotype, cardiomyocytes from iPSCs derived from Fabry-affected individuals showed accumulation of the glycosphingolipid Globotriaosylceramide (GB3), which is an α-galactosidase substrate. Furthermore, the Fabry cardiomyocytes displayed significant upregulation of lysosomal-associated proteins. Upon GLA modRNA treatment, a subset of lysosomal proteins were partially restored to wild-type levels, implying the rescue of the molecular phenotype associated with the Fabry genotype. Importantly, a significant reduction of GB3 levels was observed in GLA modRNA-treated cardiomyocytes, demonstrating that α-GAL enzymatic activity was restored. Together, our results validate the utility of iPSC-derived cardiomyocytes from affected individuals as a model to study disease processes in Fabry disease and the therapeutic potential of GLA modRNA treatment to reduce GB3 accumulation in the heart.

The histone methyltransferase SETD2 negatively regulates cell size.

Cell size varies between cell types but is tightly regulated by cell intrinsic and extrinsic mechanisms. Cell size control is important for cell function, and changes in cell size are frequently observed in cancer. Here, we uncover a role for SETD2 in regulating cell size. SETD2 is a lysine methyltransferase and a tumor suppressor protein involved in transcription, RNA processing and DNA repair. At the molecular level, SETD2 is best known for associating with RNA polymerase II through its Set2-Rbp1 interacting (SRI) domain and methylating histone H3 on lysine 36 (H3K36) during transcription. Using multiple independent perturbation strategies, we identify SETD2 as a negative regulator of global protein synthesis rates and cell size. We provide evidence that overexpression of the H3K36 demethylase KDM4A or the oncohistone H3.3K36M also increase cell size. In addition, ectopic overexpression of a decoy SRI domain increased cell size, suggesting that the relevant substrate is engaged by SETD2 via its SRI domain. These data add a central role of SETD2 in regulating cellular physiology and warrant further studies on separating the different functions of SETD2 in cancer development.

Dynamic chromosomal interactions and control of heterochromatin positioning by Ki-67.

Ki-67 is a chromatin-associated protein with a dynamic distribution pattern throughout the cell cycle and is thought to be involved in chromatin organization. The lack of genomic interaction maps has hampered a detailed understanding of its roles, particularly during interphase. By pA-DamID mapping in human cell lines, we find that Ki-67 associates with large genomic domains that overlap mostly with late-replicating regions. Early in interphase, when Ki-67 is present in pre-nucleolar bodies, it interacts with these domains on all chromosomes. However, later in interphase, when Ki-67 is confined to nucleoli, it shows a striking shift toward small chromosomes. Nucleolar perturbations indicate that these cell cycle dynamics correspond to nucleolar maturation during interphase, and suggest that nucleolar sequestration of Ki-67 limits its interactions with larger chromosomes. Furthermore, we demonstrate that Ki-67 does not detectably control chromatin-chromatin interactions during interphase, but it competes with the nuclear lamina for interaction with late-replicating DNA, and it controls replication timing of (peri)centromeric regions. Together, these results reveal a highly dynamic choreography of genome interactions and roles for Ki-67 in heterochromatin organization.

Diffuse Large B-Cell Lymphoma in a Cynomolgus Monkey.

A captive 17-year-old male cynomolgus monkey (Macaca fascicularis) developed diffuse large B-cell lymphoma (DLBCL). This was the first report of DLBCL presenting with a mandible mass and violation of the paranasal sinus in a cynomolgus monkey. The neoplasm showed marked microscopical malignant aspects. Immunohistochemical staining showed strong positive expression of CD20. These features may contribute to the diagnosis and therapeutics of DLBCL in NHPs.

Impairment of DNA Methylation Maintenance Is the Main Cause of Global Demethylation in Naive Embryonic Stem Cells.

Global demethylation is part of a conserved program of epigenetic reprogramming to naive pluripotency. The transition from primed hypermethylated embryonic stem cells (ESCs) to naive hypomethylated ones (serum-to-2i) is a valuable model system for epigenetic reprogramming. We present a mathematical model, which accurately predicts global DNA demethylation kinetics. Experimentally, we show that the main drivers of global demethylation are neither active mechanisms (Aicda, Tdg, and Tet1-3) nor the reduction of de novo methylation. UHRF1 protein, the essential targeting factor for DNMT1, is reduced upon transition to 2i, and so is recruitment of the maintenance methylation machinery to replication foci. Concurrently, there is global loss of H3K9me2, which is needed for chromatin binding of UHRF1. These mechanisms synergistically enforce global DNA hypomethylation in a replication-coupled fashion. Our observations establish the molecular mechanism for global demethylation in naive ESCs, which has key parallels with those operating in primordial germ cells and early embryos.

CBX2 shapes chromatin accessibility promoting AML via p38 MAPK signaling pathway.

BACKGROUND: The dynamic epigenome and proteins specialized in the interpretation of epigenetic marks critically contribute to leukemic pathogenesis but also offer alternative therapeutic avenues. Targeting newly discovered chromatin readers involved in leukemogenesis may thus provide new anticancer strategies. Accumulating evidence suggests that the PRC1 complex member CBX2 is overexpressed in solid tumors and promotes cancer cell survival. However, its role in leukemia is still unclear. METHODS: We exploited reverse genetic approaches to investigate the role of CBX2 in human leukemic cell lines and ex vivo samples. We also analyzed phenotypic effects following CBX2 silencing using cellular and molecular assays and related functional mechanisms by ATAC-seq and RNA-seq. We then performed bioinformatic analysis of ChIP-seq data to explore the influence of histone modifications in CBX2-mediated open chromatin sites. Lastly, we used molecular assays to determine the contribution of CBX2-regulated pathways to leukemic phenotype. RESULTS: We found CBX2 overexpressed in leukemia both in vitro and ex vivo samples compared to CD34+ cells. Decreased CBX2 RNA levels prompted a robust reduction in cell proliferation and induction of apoptosis. Similarly, sensitivity to CBX2 silencing was observed in primary acute myeloid leukemia samples. CBX2 suppression increased genome-wide chromatin accessibility followed by alteration of leukemic cell transcriptional programs, resulting in enrichment of cell death pathways and downregulation of survival genes. Intriguingly, CBX2 silencing induced epigenetic reprogramming at p38 MAPK-associated regulatory sites with consequent deregulation of gene expression. CONCLUSIONS: Our results identify CBX2 as a crucial player in leukemia progression and highlight a potential druggable CBX2-p38 MAPK network in AML.

The relationship between UGT1A1 gene & various diseases and prevention strategies.

UDP-glucuronyltransferase 1A1 (UGT1A1) is a member of the Phase II metabolic enzyme family and the only enzyme that can metabolize detoxified bilirubin. Inactivation and very low activity of UGT1A1 in the liver can be fatal or lead to lifelong Gilbert's syndrome (GS) and Crigler-Najjar syndrome (CN). To date, more than one hundred UGT1A1 polymorphisms have been discovered. Although most UGT1A1 polymorphisms are not fatal, which diseases might be associated with low activity UGT1A1 or UGT1A1 polymorphisms? This scientific topic has been studied for more than a hundred years, there are still many uncertainties. Herein, this article will summarize all the possibilities of UGT1A1 gene-related diseases, including GS and CN, neurological disease, hepatobiliary disease, metabolic difficulties, gallstone, cardiovascular disease, Crohn's disease (CD) obesity, diabetes, myelosuppression, leukemia, tumorigenesis, etc., and provide guidance for researchers to conduct in-depth study on UGT1A1 gene-related diseases. In addition, this article not only summarizes the prevention strategies of UGT1A1 gene-related diseases, but also puts forward some insights for sharing.

Predicting rifampicin resistance mutations in bacterial RNA polymerase subunit beta based on majority consensus.

BACKGROUND: Mutations in an enzyme target are one of the most common mechanisms whereby antibiotic resistance arises. Identification of the resistance mutations in bacteria is essential for understanding the structural basis of antibiotic resistance and design of new drugs. However, the traditionally used experimental approaches to identify resistance mutations were usually labor-intensive and costly. RESULTS: We present a machine learning (ML)-based classifier for predicting rifampicin (Rif) resistance mutations in bacterial RNA Polymerase subunit ß (RpoB). A total of 186 mutations were gathered from the literature for developing the classifier, using 80% of the data as the training set and the rest as the test set. The features of the mutated RpoB and their binding energies with Rif were calculated through computational methods, and used as the mutation attributes for modeling. Classifiers based on five ML algorithms, i.e. decision tree, k nearest neighbors, naïve Bayes, probabilistic neural network and support vector machine, were first built, and a majority consensus (MC) approach was then used to obtain a new classifier based on the classifications of the five individual ML algorithms. The MC classifier comprehensively improved the predictive performance, with accuracy, F-measure and AUC of 0.78, 0.83 and 0.81for training set whilst 0.84, 0.87 and 0.83 for test set, respectively. CONCLUSION: The MC classifier provides an alternative methodology for rapid identification of resistance mutations in bacteria, which may help with early detection of antibiotic resistance and new drug discovery.

[Study on synergistic anti-tumor effect of Shuangdan Capsules combined with 5-FU on hepatocellular carcinoma cells Huh-7 and xenograft mice].

This paper discussed the synergistic anti-tumor effect of Shuangdan Capsules combined with 5-fluorouracil(5-FU) on human liver cancer cell line Huh-7 and tumor bearing mice. The effects of Shuangdan Capsules combined with 5-FU on the activity and vascular endothelial growth factor(VEGF) receptor protein expression of Huh-7 cells were investigated, and the effects of drug combination on tube formation of HUVEC cell were also verified. In addition, the mice model of Huh-7 was established to observe the anti-tumor effect of drug combination and the distribution of tumor blood flow in tumor bearing mice by using molecular imaging. HPLC analysis showed that Shuangdan Capsules mainly consisted of danshensusodium, protocatechuic aldehyde, paeoniflorin, rosmarinic acid, alkannic acid, salvianolic acid B, and paeonol. In MTT experiment, the inhibition rate of Shuangdan Capsules(20 mg·L~(-1)) and 5-FU(1 µmol·L~(-1)) on Huh-7 cells was 60%, and the CI value was 0.59, suggesting that these two drugs had synergistic anti-hepatoma cells effect. The expression of VEGF receptor in Huh-7 cells was inhibited by the combination of these two drugs. In addition, the process of HUVEC was slow, and the number, length and area of the lumen branches decreased significantly. In vivo, Shuangdan Capsules combined with 5-FU inhibited the growth and prolongation of survival of Huh-7 cells in subcutaneous transplanted tumor nude mice; serum expression of CD31 and VEGF in nude mice were decreased, while caspase-3 was increased. Meanwhile, the drug combination significantly inhibited the expressions of MMP2 and VEGF in tumor tissues. Ultrasound showed that Shuangdan Capsules combined with 5-FU also inhibited tumor angiogenesis and reduced blood flow of tumor tissue. The results showed that Shuangdan Capsules combined with 5-FU may inhibit tumor angiogenesis by inhibiting VEGF and MMP2 expressions, thereby blocking tumor growth.

[Effect of lupeol on invasion and metastasis of human hepatoma HepG2 and SK-HEP-1 cells and its mechanism].

Epithelial-mesenchymal transformation(EMT) exists in embryonic development and is closely related to cell migration and invasion. The increased EMT level in tumors showed that E-cadherin was replaced by N-cadherin, and the expression of interstitial markers such as α-SMA and vimentin was up-regulated. It has been reported that lupeol can reduce the expression of matrix metalloproteinase-2(MMP-2), matrix metalloproteinase-9(MMP-9) and N-cadherin to inhibit the metastasis of osteoma cells. However lupeol has been less studied in liver cancer. Therefore, this paper investigated the effect of lupanol on invasion and metastasis of human hepatoma cell line HepG2 and SK-HEP-1 and its possible mechanism. MTT assay and Annexin V/PI double staining were used to investigate the effect of lupeol on activity and apoptosis of HepG2 cells and SK-HEP-1 cells. Moreover, the effect of lupeol on the invasion of HepG2 cells and SK-HEP-1 cells were evaluated by Transwell assay. The expressions of E-cadherin, N-cadherin, α-SMA, vimentin and MMP-9 were measured by Western blot. The model of subcutaneous transplantation of nude mice and the lung metastasis model of H22 hepatocellular carcinoma cells were established to evaluate the efficacy of lupeol in vivo on tumor growth and lung metastasis by HE staining combined with immunohistochemical assay. The results showed that lupeol inhibited the activity and invasion of HepG2 cells and SK-HEP-1 cells in a dose-dependent manner and induced apoptosis. Western blot showed that the expression of E-cadherin, a landmark protein for EMT, was induced by lupeol, and the expressions of N-cadherin, α-SMA, vimentin and MMP-9 were decreased. In vivo experiments showed that lupeol inhibited tumor growth in mice bearing xenograft. In addition, immunohistochemical experiments confirmed that lupeol could up-regulate the expression of E-cadherin in tumor tissues of nude mice, reduce the expression of N-cadherin, and inhibit the metastasis of liver cancer H22 cells in the lungs of mice. The above results indicated that the mechanism of lupeol inhibiting the invasion and metastasis of HCC cells may be related to the regulation of EMT process.

Ferritin heavy chain in triple negative breast cancer: a favorable prognostic marker that relates to a cluster of differentiation 8 positive (CD8+) effector T-cell response.

Ferritin heavy chain (FTH1) is a 21-kDa subunit of the ferritin complex, known for its role in iron metabolism, and which has recently been identified as a favorable prognostic protein for triple negative breast cancer (TNBC) patients. Currently, it is not well understood how FTH1 contributes to an anti-tumor response. Here, we explored whether expression and cellular compartmentalization of FTH1 correlates to an effective immune response in TNBC patients. Analysis of the tumor tissue transcriptome, complemented with in silico pathway analysis, revealed that FTH1 was an integral part of an immunomodulatory network of cytokine signaling, adaptive immunity, and cell death. These findings were confirmed using mass spectrometry (MS)-derived proteomic data, and immunohistochemical staining of tissue microarrays. We observed that FTH1 is localized in both the cytoplasm and/or nucleus of cancer cells. However, high cytoplasmic (c) FTH1 was associated with favorable prognosis (Log-rank p = 0.001), whereas nuclear (n) FTH1 staining was associated with adverse prognosis (Log-rank p = 0.019). cFTH1 staining significantly correlated with total FTH1 expression in TNBC tissue samples, as measured by MS analysis (Rs = 0.473, p = 0.0007), but nFTH1 staining did not (Rs = 0.197, p = 0.1801). Notably, IFN γ-producing CD8+ effector T cells, but not CD4+ T cells, were preferentially enriched in tumors with high expression of cFTH1 (p = 0.02). Collectively, our data provide evidence toward new immune regulatory properties of FTH1 in TNBC, which may facilitate development of novel therapeutic targets.

[Anti-inflammatory effect of recombinant human kallistatin in ulcerative colitis of mice].

This study was designed to evaluate the anti-inflammatory effect of recombinant human kallistatin (Kal) on ulcerative colitis (UC) in the mouse model. Acute colitis was induced by administration of 4% dextran sodium suffate (DSS) to KM mice for 7 days. The mice were then randomized into 5 groups: model control, Kal 0.2 mg·kg(-1)·d(-1), 1.0 mg·kg(-1)·d(-1) and 2.0 mg·kg-1·d(-1) group, salazosulfapyridine (SASP) group. Ten age-matched normal KM mouse were administered with saline in the normal control. The weight, colon length, inflammation factor (MPO/SOD/MDA) and TNF-α/IL-10 levels among the five groups of mice were determined. The results showed that histological index score and MPO/MDA/TNF-α levels of high-dose Kal treatment group and SASP group were significantly lower compared with the model group (P < 0.01), but the weight, colon length, IL-10 level and SOD activity were significant higher than the model group (P < 0.01), approaching the normal group. These parameters showed that Kal can significantly relieve the UC state in a dose-dependent manner. This study demonstrates that Kal significantly remits UC in mice, and participates in the regulation of inflammatory cytokines TNF-α/IL-10 levels and has some antioxidant activity.

[Relationship between hepatic drug-metabolizing enzymes CYP450 and traditional Chinese medicine-induced hepatotoxicity].

In recent years, with the emergence of new methods and technologies in traditional Chinese medicines metabolism, the relationship between medicine metabolism and cytochrome P450 has gradually been revealed. The research on P450 drug metabolizing enzymes can be used to predict the side effects of traditional Chinese medicines and explore the relationship between compatibility of medicines and toxicity reducing and efficacy enhancing. This paper aims to summarize the progress of CYP450 research, the mechanism of hepatic drug-metabolizing enzymes in the process of drug-metabolism and the relationship between CYP450 and medicine hepatotoxicity. Furthermore, we set out the regulation effects of typical traditional Chinese medicines on CYP450 to provide a reliable basis for the rational use of Chinese medicines.

Effects of liraglutide on left ventricular function in patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention.

BACKGROUND: Several studies have shown that exenatide protects against ischemia-reperfusion injury and improves cardiac function in patients with acute ST-segment elevation myocardial infarction (STEMI). The effects of liraglutide, a glucagon-like peptide-1 analogue, on STEMI patients remain unclear. We planned to evaluate the effects of liraglutide on left ventricular function after primary percutaneous coronary intervention for STEMI. METHODS: A total of 92 patients were randomized 1:1 to receive either liraglutide or placebo for 7 days. Study treatment was commenced 30 minutes before intervention (1.8 mg) and maintained for 7 days after the procedure (0.6 mg for 2 days, 1.2 mg for 2 days, followed by 1.8 mg for 3 days). Eighty-five patients completed the trial. Transthoracic echocardiography was used to assess left ventricular function. RESULTS: At 3 months, the primary end point, a difference in change of left ventricular ejection fraction between the two groups was +4.1% (95% CI +1.1% to +6.9%) (P < .001). There was a tendency for a lower rate of no-reflow in liraglutide group that did not reach statistical significance (7% vs control group 15%, P = .20). Liraglutide could significantly improve stress hyperglycemia (P < .05). In addition, liraglutide elicited favorable changes in markers of inflammation and endothelial function. CONCLUSION: A short 7-day course of liraglutide in STEMI patients treated with primary percutaneous coronary intervention is associated with mild improvement in left ventricular ejection fraction at 3 months.

Expression of B and T lymphocyte attenuator (BTLA) in macrophages contributes to the fulminant hepatitis caused by murine hepatitis virus strain-3.

OBJECTIVES: Fulminant viral hepatitis (FH) remains a serious clinical problem for which the underlying pathogenesis remains unclear. The B and T lymphocyte attenuator (BTLA) is an immunoglobulin-domain-containing protein that has the capacity to maintain peripheral tolerance and limit immunopathological damage during immune responses. However, its precise role in FH has yet to be investigated. DESIGN: BTLA-deficient (BTLA-/-) mice and their wild-type littermates were infected with murine hepatitis virus strain-3 (MHV-3), and the levels of tissue damage, cell apoptosis, serum liver enzymes, fibrinogen-like protein 2 (FGL2) and cytokine production were measured and compared. Survival rate was studied after MHV-3 infection with or without adoptive transferring macrophages. RESULTS: FGL2 production, liver and spleen damage, and mortality were significantly reduced in BTLA-/- mice infected with MHV-3. This effect is due to rapid, TRAIL (TNF-related apoptosis-inducing ligand)-dependent apoptosis of MHV-3-infected macrophages in BTLA-/- mice. The early loss of macrophages resulted in reduced pathogenic tumour necrosis factor α (TNFα) and FGL2 levels and lower viral titres. The importance of TNFα in MHV-3-induced pathology was demonstrated by increased mortality in TNFα-treated MHV-3-infected BTLA-/- mice, whereas TNFα-/- mice were resistant to the infection. Moreover, adoptively transferring macrophages to BTLA-/- mice caused sensitisation, whereas blocking BTLA protected wild-type mice from virus-induced FH mortality. CONCLUSIONS: BTLA promotes the pathogenesis of virus-induced FH by enhancing macrophage viability and function. Targeting BTLA may be a novel strategy for the treatment of FH.

Sulfated hyaluronic acid gel for the treatment of rheumatoid arthritis in rats.

Rheumatoid arthritis (RA) is a chronic autoimmune disease. NSAIDS, cyclophosphamide and glucocorticoid were commonly used to treat RA in clinical application, which long-term administration of these drugs caused serious adverse reactions. Therefore, sulfated hyaluronic acid (sHA) gel (SG) was prepared to firstly treat the RA and avoid the problem of toxic side effect caused by long-term application. In vitro evaluation showed that sHA inhibited the level of reactive oxygen species and TNF-α, IL-1ß, and IL-6, and decreased the ratio of macrophage M1/M2 type, which exerted better anti-inflammatory capacity. In vivo studies showed that the injection of SG into the joint cavity of collagen-induced rheumatoid arthritis (CIA) rats could effectively treat joint swelling and reduce the level of inflammatory factors in the serum. Immunofluorescence showed that SG exerted its anti-inflammatory activity by decreasing the ratio of M1/M2 type macrophages in synovial tissue. Cartilage tissue sections showed that SG reduced bone erosion and elevated chondrocyte expression. These results confirmed that sHA is expected to be developed as a drug to treat or relieve RA, which could effectively regulate the level of macrophages in rat RA, alleviate the physiological state of inflammatory over-excitation, and improve its anti-inflammatory and antioxidant capacity.

Isolation and Identification of Morganella morganii from Rhesus Monkey (Macaca mulatta) in China.

A bacterium was isolated and identified from the secretion of a rhesus monkey with endometritis. The morphological results showed that the strain exhibited round, convex, gray-white colonies with smooth surfaces and diameters ranging from 1 to 2 mm when cultured on Columbia blood agar at 37 °C for 24 h; on salmonella-shigella agar (S.S.) at 37 °C for 24 h, the colonies appeared round, flat, and translucent. Gram staining showed negative results with blunt ends and non-spore-forming characteristics. Molecular biology results showed that the 16S rRNA sequence of the strain revealed over 96.9% similarity with published sequences of M. morganii from different sources in the NCBI GenBank database. Morphological and molecular biology analysis confirmed that the strain (RM2023) isolated from cervical secretions of rhesus monkey was M. morganii. Drug sensitivity testing demonstrated that the isolated strain (RM2023) was sensitive to ceftriaxone, amikacin, gentamicin, cefazolin, cefuroxime, ceftazidime, levofloxacin, cotrimoxazole, norfloxacin, and tetracycline; moderately sensitive to ampicillin; and resistant to penicillin, vancomycin, ciprofloxacin, and clindamycin. The research findings provide valuable insights for disease prevention in rhesus monkeys and contribute to molecular epidemiological studies.

Function-oriented mechanism discovery of coumarins from Psoralea corylifolia L. in the treatment of ovariectomy-induced osteoporosis based on multi-omics analysis.

ETHNOPHARMACOLOGICAL RELEVANCE: Psoraleae Fructus (Bu Gu Zhi) is the fruit of Psoralea corylifolia L. (PCL) and has been used for centuries in traditional Chinese medicine formulas to treat osteoporosis (OP). A new drug called "BX" has been developed from PCL, but its mechanism for treating OP is not yet fully understood. AIM OF THE STUDY: To explore the mechanism of action of BX in the treatment of ovariectomy-induced OP based function-oriented multi-omics analysis of gut microbiota (GM) and metabolites. MATERIALS AND METHODS: C57BL/6 mice were bilaterally ovariectomized to replicate the OP model. The therapeutic efficacy of BX was evaluated by bone parameters (BMD, BV/TV, Tb.N, Tb.Sp), hematoxylin and eosin (H&E) staining results, and determination of bone formation markers procollagen type Ⅰ amino-terminal peptide (PⅠNP) and bone-specific alkaline phosphatase (BALP). Serum and fecal metabolomics and high-throughput 16S rDNA sequencing were performed to evaluate effects on endogenous metabolites and GM. In addition, an enzyme-based functional correlation algorithm (EBFC) algorithm was used to investigate functional correlations between GM and metabolites. RESULTS: BX improved OP in OVX mice by increasing BMD, BV/TV, serum PⅠNP, BALP, and improving Tb.N and Tb.Sp. A total of 59 differential metabolites were identified, and 9 metabolic pathways, including arachidonic acid metabolism, glycerophospholipid metabolism, purine metabolism, and tryptophan metabolism, were found to be involved in the progression of OP. EBFC analysis results revealed that the enzymes related to purine and tryptophan metabolism, which are from Lachnospiraceae_NK4A136_group, Blautia, Rs-E47_termite_group, UCG-009, and Clostridia_UCG-014, were identified as the intrinsic link between GM and metabolites. CONCLUSIONS: The regulation of GM and restoration of metabolic disorders may be the mechanisms of action of BX in alleviating OP. This research provides insights into the function-oriented mechanism discovery of traditional Chinese medicine in the treatment of OP.