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Fracture-healing effects of Rhizoma Musae ethanolic extract: An integrated study using UHPLC-Q-Exactive-MS/MS, network pharmacology, and molecular docking

  • Jian Zhang ,

    Roles Funding acquisition, Methodology, Writing – original draft, Writing – review & editing

    nkyzhangjian@163.com

    Affiliation GuiZhou Institute of Subtropical Crops, Guizhou Academy of Agricultural Sciences, Guiyang, China

  • Wanyan Shen,

    Roles Methodology, Supervision

    Affiliation Research and Development Department, Guizhou Weikang Zifan Pharmaceutical Co., Ltd., Guiyang, China

  • Fanzhi Liu,

    Roles Funding acquisition, Methodology, Writing – review & editing

    Affiliation GuiZhou Institute of Subtropical Crops, Guizhou Academy of Agricultural Sciences, Guiyang, China

  • Hehe He,

    Roles Data curation, Investigation

    Affiliation Research and Development Department, Guizhou Weikang Zifan Pharmaceutical Co., Ltd., Guiyang, China

  • Shuquan Han,

    Roles Funding acquisition, Writing – review & editing

    Affiliation GuiZhou Institute of Subtropical Crops, Guizhou Academy of Agricultural Sciences, Guiyang, China

  • Lina Luo

    Roles Funding acquisition, Writing – review & editing

    Affiliation GuiZhou Institute of Subtropical Crops, Guizhou Academy of Agricultural Sciences, Guiyang, China

Abstract

Background

Fracture disrupts the integrity and continuity of the bone, leading to symptoms such as pain, tenderness, swelling, and bruising. Rhizoma Musae is a medicinal material frequently utilized in the Miao ethnic region of Guizhou Province, China. However, its specific mechanism of action in treating fractures remains unknown. This study aimed to elucidate the chemical constituents of the ethanol extract of Rhizoma Musae (EERM) and investigate its fracture-healing mechanism using network pharmacology.

Methods

The chemical profile of EERM was characterized via UHPLC-Q-Exactive-MS/MS. Subsequently, a comprehensive network of compounds, targets, and pathways was constructed using network pharmacology approaches. The interactions between the active compounds of EERM and their targets were validated through molecular docking, molecular dynamics simulation and in vitro cell experiments.

Results

EERM contained 522 identified compounds. Topological analysis of the protein-protein interaction (PPI) network identified 59 core targets, including key proteins like AKT1, IL-6, and EGFR, known for their anti-inflammatory properties and ability to enhance bone cell proliferation and differentiation. Gene Ontology analysis indicated the involvement of EERM in biological processes such as peptidyl-serine phosphorylation, response to xenobiotic stimulus, and nutrient level regulation. KEGG analysis suggested that EERM’s mechanism may involve signaling pathways such as PI3K-Akt, lipid and atherosclerosis, EGFR tyrosine kinase inhibitor resistance, and MAPK pathways. Molecular docking and molecular dynamics simulations results demonstrated a strong binding affinity between the main compounds of EERM and key targets. In vitro cell experiments demonstrate that EERM enhances cell proliferation by upregulating the expression levels of EGFR and STAT3, while simultaneously downregulating AKT1 and CASP3.

Conclusion

This study investigates the potential active compounds of EERM and its key targets in regulating multiple pathways of fracture, leading to promoting bone cell proliferation. These results offer valuable insights for the future development and clinical application of Rhizoma Musae.

1. Introduction

The dried rhizome of Musa basjoo Sieb. et Zucc., referred to as Rhizoma Musae, is integral to the traditional medicine of the Miao ethnic group in Guizhou Province, China. Recognized for its therapeutic efficacy, Rhizoma Musae is listed in the "Quality Standards of Traditional Chinese and Ethnic Medicinal Materials in Guizhou Province" (2019) [1]. Prior phytochemical analyses have identified numerous compounds in Rhizoma Musae, including volatile oils, phenols, phenalenone, alkaloids, and acenaphthene derivatives [2]. These constituents are renowned for their pharmacological effects, such as anti-inflammatory, antibacterial, and bone formation-promoting properties [3].

The bone is a composite structure composed of cortical bone and trabecular bone, and it contains components such as hydroxyapatite, collagen, a small amount of proteoglycan, non-collagen proteins, and water [4]. Cortical bone provides strength and stability, while trabecular bone offers flexibility and support. Fractures, which disrupt bone integrity and continuity, present symptoms like pain, tenderness, swelling, and bruising, with the possibility of bone deformation and abnormal movements [5]. The risk of fractures varies significantly among different groups, influenced by factors such as fracture type, demographics, age, and obesity [6]. Osteoblasts exist in cortical bone and are mainly generated from bone mesenchymal stem cells. The process of fracture healing requires osteoclasts to remove old or damaged bone, and then osteoblasts replace it with new bone [7]. Osteoblasts also secrete growth factors and cytokines that regulate bone remodeling and repair [8]. Therefore, osteoblasts are important guardians of bone health and play a crucial role in the growth, development, and repair of bones.

Traditional Chinese Medicine (TCM) offers notable benefits in fracture healing, primarily due to its anti-inflammatory [9] and antioxidant properties [10], with a low side effect profile, underscoring its role in fracture management [11]. The Gukang capsule, containing Rhizoma Musae as a principal ingredient, has demonstrated efficacy in treating osteoporosis, fractures, and related injuries [12]. Preliminary studies indicate that the ethanolic extract of Rhizoma Musae (EERM) promotes bone cell growth and differentiation, as evidenced by elevated levels of alkaline phosphatase (ALP), Ca2+, and osteocalcin secretion [13]. Nevertheless, the precise molecular mechanisms underpinning these medicinal benefits remain to be elucidated.

Network pharmacology, a burgeoning discipline grounded in systems biology, network analysis of biological systems, and targeted signal node selection for multi-target drug design, is pivotal in elucidating the mechanisms of TCM, thereby facilitating their extensive exploration and clinical application [14]. This study utilized UHPLC-Q-Exactive-MS/MS technology to analyze the chemical compounds of EERM and investigated its mechanism in fracture treatment through network pharmacology and molecular docking. These insights are vital for future clinical trials and the advancement of pharmaceutical research in this domain.

2. Materials and methods

2.1 Experimental instruments

The primary equipment comprised an ultra-high-pressure liquid chromatograph (Vanquish, Thermo Fisher Scientific, USA), a Q Exactive HFX mass spectrometer (Thermo Fisher Scientific), a UHPLC-Q Exactive HFX, and an ultra-high-performance liquid chromatography-tandem static orbitrap mass spectrometer (Thermo Fisher Scientific), a Centrifuge 5430 R (Eppendorf, Germany), an SCI-VS vortex mixer (Scilogex, USA), an ultrasonic cleaner SB25-12DTD (Ningbo Xinzhi Biotechnology Co., Ltd., China), SpectraMax M5/M5e multiscan spectrum (Molecular Devices, USA), CO2 incubator (Thermo Fisher, USA), and CFX384 Multiple real-time fluorescent quantitative PCR apparatus (Bio-Rad, USA).

2.2 Chemical reagents

The study utilized coarse Rhizoma Musae powder provided by Guizhou Weikang Zifan Pharmaceutical Co., Ltd. (batch number YC01-003-20230801). The solvents employed in the extraction and analysis processes included methanol, acetonitrile, formic acid, and isopropanol (all of the analytical grade, Anpu), as well as 95% ethanol (analytical grade) procured from Sangon (Shanghai, China), and ultrapure water. Human Osteoblasts hFOB1.19 (Shanghai Cell Bank, Chinese Academy of Sciences, China). DMEM/F12 (Gibco, USA). Fetal Bovine Serum (Gibco, USA); PBS (Sangon, ShangHai). 0.25% Trypsin-EDTA (Thermo Fisher, USA). TRIzol Plus RNA Purification Kit(Thermo Fisher, USA). RNase-Free DNase Set (Qiagen, Germany). CCK-8 (Tongren Institute of Chemistry, Japan).

2.3 Chemical composition analysis of EERM

2.3.1 Sample preparation.

During the preparatory phase, 1 g of coarse Rhizoma Musae herb powder was initially immersed in 2 mL of 45% ethanol for 30 minutes to ensure thorough saturation. Subsequently, the sample underwent further extraction in 8 mL of 45% ethanol for 6 hours. After this period, 1 mL of the resulting supernatant was combined with 2 mL of a methanol-acetonitrile (1:1, v/v) solution, vortexed for 60 seconds, and sonicated at a low temperature for 30 minutes. Following sonication, the mixture was centrifuged at 12,000 rpm for 10 minutes at 4°C. The supernatant was then extracted and subjected to chilling at −20°C for 1 hour to precipitate proteins. Another round of centrifugation under the same conditions was performed, after which the supernatant was collected, lyophilized, and reconstituted in 100 μL of 50% acetonitrile. Finally, the vortexed sample was centrifuged again at 12,000 rpm for 10 minutes at 4°C, and the supernatant was collected for analysis.

2.3.2 Analytical conditions.

Chromatographic conditions: Liquid chromatography was conducted using a Waters HSS T3 column (100 × 2.1 mm, 1.8 μm), with the column temperature maintained at 40°C to ensure optimal separation. The mobile phase comprised Phase A (0.1% formic acid in water) and Phase B (0.1% formic acid in acetonitrile), with a flow rate of 0.3 mL/min. The elution protocol commenced with 0% Phase B for 1 minute, gradually increasing to 95% Phase B over the next 11 minutes, maintaining 95% Phase B for 1 minute, then swiftly returning to 0% Phase B within 0.1 minutes, and finally holding at 0% Phase B for 3.9 minutes. Samples were preserved at 4°C in an autosampler throughout the analysis, with an injection volume of 2 μL.

Mass spectrometry protocols: Primary and secondary spectral data were acquired using a Q Exactive HFX high-resolution mass spectrometer, utilizing Electrospray Ionization under specific conditions: sheath gas flow at 40 units, auxiliary gas flow at 10 arbitrary units, ion spray voltage set to 3000 V/−2800 V, capillary temperature at 350°C, and ion transfer tube temperature at 320°C. The system, in Full-ms-ddMS2 mode, detected ions in both positive and negative modes across a mass range of 70–1,050 Da, achieving resolutions of 70,000 and 17,500 for primary and secondary scans, respectively. The compounds were characterized based onthe Sanshu Biotech’s proprietary database, specialized in TCM, and their unique secondary mass spectrometry fragmentation pattern matching technique. The relative contents of each compound in EERM were obtained by the area normalization method.

2.4 Network pharmacology research

2.4.1 Identification of EERM-related targets.

The chemical constituents of EERM and their structures were sourced from the NCBI PubChem database (https://pubchem.ncbi.nlm.nih.gov/). The isomeric SMILES structures of these constituents were uploaded to the Swiss Target Prediction database (http://www.swisstargetprediction.ch/) for target prediction. Additionally, the UniProt database (https://www.uniprot.org/) was utilized to standardize gene nomenclature, thereby aiding in the identification of drug targets associated with EERM.

2.4.2 Identification of fracture targets and construction of protein-protein interaction (PPI) network.

To identify fracture-related targets, the term "Fracture" was searched across three genetic databases pertinent to diseases: GeneCards (https://www.genecards.org/), Comparative Toxicogenomics Database (CTD; https://ctdbase.org/), and the Online Mendelian Inheritance in Man (OMIM) database (https://www.omim.org/). The collected data underwent organization and deduplication to create a comprehensive list of fracture-related disease targets.

The online tool Venny (https://bioinfogp.cnb.csic.es/tools/venny/) facilitated the identification of common targets between the active compounds of EERM and known fracture-related targets by intersecting their respective targets. These common targets were further analyzed using the STRING database (https://cn.string-db.org/) with a minimum interaction score of ≥ 0.4. The resultant protein-protein interaction (PPI) network map and TSV format files were subsequently analyzed using Cytoscape software (version 3.9.0) for topological analysis, culminating in a detailed network diagram of "drug compounds-targets-fracture."

2.4.3 Enrichment analyses for GO functions and KEGG pathways.

The targets were subjected to Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses using R software to investigate the potential biological functions and primary signaling pathways implicated in fracture treatment with EERM. The enrichment results were filtered to highlight significant differences and then ranked in descending order based on their P-values, with a significance threshold set at a q-value of < 0.05.

2.4.4 Molecular docking.

A greater overlap between disease treatment targets and drug action targets resulted in higher degree values in topological analysis [15]. The top five targets in the PPI network, determined by their degree value, were identified as critical for fracture treatment. Utilizing Amoxicillin as a positive control, these targets underwent molecular docking analysis with the top five core active compounds of EERM, also selected based on degree value. Core target-related protein structures in PDB format were retrieved from the RCSB PDB database (https://www.rcsb.org/), and the active component structures were sourced from the PubChem database. AutoDock Vina 1.1.2 software was utilized for preprocessing target proteins and small molecules, including format transformation and binding site analysis, to validate the docking interactions. Core targets were visually represented using PyMol software.

2.4.5 Molecular dynamics simulation.

Gromacs version 2022.03 software was utilized to conduct a 50 ns molecular dynamics (MD) simulation on the receptor protein with the highest binding energy to the ligand molecule identified in the molecular docking results. The CHARMM36 force field was employed for this simulation. The complex resulting from the molecular docking was utilized as the initial structure for the MD simulations, with the small molecule ligands being handled using the Generalized Amber Force Field. The complex was dissolved using three-point transferable intermolecular potential solvents. The solutes were contained within the isothermal isovolumetric ensemble, where the system was gradually heated from 0 K to 300 K. Subsequently, equilibration was achieved in the isothermal isobaric ensemble at a temperature of 300 K and a pressure of 1 Bar.

2.5 In vitro cell assays

2.5.1 Cell culture.

Once the hFOB1.19 cells were resuscitated, cell passage was performed when the cells reached 80% to 95% confluence. To resuspend the cells, add 0.25% Trypsin-EDTA medium that has been preheated to 37°C. Subsequently, transfer the cells to a new culture dish at a density of 5 × 105 cells/mL and continue the culturing process in a cell incubator maintained at 37°C with 5% CO2.

2.5.2 Cell proliferation assays.

Collect the hFOB1.19 cells that have reached the logarithmic phase of growth. The cells were treated with EERM at concentrations of 0, 60, 80, 100, 120, 140, and 160 μg/mL, respectively. For the control group, blank medium was used. The cells were seeded in 96-well plates, with six replicates in each group and 3 × 103 cells per well. After 48 hours of incubation, 10 μL of CCK-8 reagent was added to each well, followed by an additional incubation period of 1.5 hours. The absorbance value at 450 nm was measured using a microplate reader to calculate the cell proliferation inhibition rate for each experimental group.

2.5.3 Quantitative real-time polymerase chain reaction (qPCR).

RNA extraction from the cells was performed utilizing an RNA extraction kit, which was subsequently followed by the synthesis of cDNA. The PCR primers were created with the help of Primer Premier 6.0 and were synthesized by Sangon Biotech (Shanghai). The sequences of the primers can be found in Table 1. The conditions for PCR amplification were set at 95°C for 30 seconds, succeeded by 40 cycles of 95°C for 5 seconds and 60°C for 30 seconds. The internal reference gene used was β-actin, and the relative mRNA expression levels were determined employing the 2−△△Ct method.

2.5.4 Statistical analysis.

The experimental results were analyzed using GraphPad Prism version 10.1.2. All results are presented as mean ± SEM. An independent unpaired two-tailed t-test was employed to compare the two groups.

3. Results

3.1 Identification of EERM compounds

The study of EERM cataloged 522 compounds, as detailed in S1 Table, including 288 identified in positive ion mode and 234 in negative ion mode (Fig 1). These compounds were classified by chemical nature into the following categories: 62 flavonoids, 53 prenol lipids, 44 organooxygen compounds, 34 carboxylic acids and derivatives, 27 coumarins and derivatives, 24 fatty acyls, 20 benzene and substituted derivatives, 18 isoflavonoids, 16 cinnamic acids and derivatives, 12 phenols, 11 benzopyrans, 7 purine nucleosides, and 194 others.

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Fig 1.

Total ion chromatogram of active compounds from EERM in positive ion (A) and negative ion (B) modes.

https://doi.org/10.1371/journal.pone.0313743.g001

3.2 Acquisition of potential targets for EERM in fracture treatment

The top 70 compounds in EERM, selected based on their relative peak area (Table 2), were analyzed using the Swiss Target Prediction database, identifying 632 potential medicinal targets. Subsequent research into GeneCards, CTD, and OMIM databases identified 1,546, 5,732, and 654 fracture-related targets, respectively. Intersecting these results with drug target genes revealed 279 potential targets for fracture treatment (Fig 2).

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Fig 2. Venn diagram illustrating the intersected targets of EERM compounds and fracture.

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Table 2. Relative content analysis of the top 70 compounds found in EERM.

https://doi.org/10.1371/journal.pone.0313743.t002

3.3 Analysis of the PPI network

To investigate the interaction relationships among the 279 potential targets, these were uploaded to the STRING database, unveiling a PPI network consisting of 278 proteins and 4,788 interactions (Fig 3). Key targets were identified by applying criteria where "Degree, betweenness centrality, and closeness centrality exceeded average values," resulting in 59 core targets (S2 Table). The top 10 targets, determined by degree value (Table 3)—AKT1, IL-6, epidermal growth factor receptor (EGFR), STAT3, CASP3, HIF1A, SRC, BCL2, ESR1, and HSP90AA1—demonstrate that EERM compounds predominantly influence these core targets, thereby affecting their positive impact on fractures.

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Fig 3. Visualization of the protein-protein interaction (PPI) network of potential targets for EERM.

https://doi.org/10.1371/journal.pone.0313743.g003

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Table 3. Topological parameter analysis of the top 10 core targets.

https://doi.org/10.1371/journal.pone.0313743.t003

3.4 Development of the "EERM-Fracture" network diagram

The "EERM-Fracture" network diagram (Fig 4) was constructed using Cytoscape software (version 3.9.0), with the Network Analyzer plugin employed for topological parameter analysis. The analysis revealed an average adjacency of 6.383 nodes, network heterogeneity of 2.712, a network density of 0.02, and a centrality measure of 0.849. Nodes with higher degree values were identified as central nodes, with the five most active compounds being 4′-hydroxy-2-O-methylanigorufone (degree = 57), Syringolin A (degree = 54), 7β-Hydroxyrutaecarpine (degree = 53), linoleic acid (degree = 51), and Hydroxyanigorufone (degree = 50; Table 4), highlighting their critical roles within the network.

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Fig 4. Schematic representation of the "Component-target-pathway" network illustrating the mechanism of EERM.

Drug compounds are depicted as blue diamonds, targets are shown as green circles, and signaling pathways are indicated as yellow squares.

https://doi.org/10.1371/journal.pone.0313743.g004

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Table 4. Top 10 active compounds in EERM with potential efficacy against fractures.

https://doi.org/10.1371/journal.pone.0313743.t004

3.5 GO analysis and KEGG pathway enrichment analysis

The "Cluster Profiler" package in R software facilitated the GO enrichment analysis of 279 potential targets, resulting in the identification of 3,266 entries (Fig 5). Within these, the biological process (BP) category comprised 2,900 entries, primarily involving peptidyl-serine phosphorylation, response to xenobiotic stimulus, response to nutrient levels, peptidyl-serine modification, and response to steroid hormone. The cellular component (CC) category included 136 entries, predominantly associated with the membrane raft, membrane microdomain, neuronal cell body, apical part of the cell, and vesicle lumen. The molecular function (MF) category featured 230 entries, focusing on protein serine/threonine kinase activity, protein serine kinase activity, nuclear receptor activity, ligand-activated transcription factor activity, and protein tyrosine kinase activity.

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Fig 5. Gene Ontology functional enrichment analysis results for the potential targets of EERM.

https://doi.org/10.1371/journal.pone.0313743.g005

Subsequent KEGG pathway enrichment analysis on 279 potential targets, conducted using the "Cluster Profiler" package in R, identified 169 significant signaling pathways (q-value < 0.05; Fig 6). This analysis notably highlighted pathways related to prostate cancer, lipid metabolism and atherosclerosis, resistance to EGFR tyrosine kinase inhibitors (TKIs), the PI3K-Akt signaling pathway, chemical carcinogenesis via receptor activation, endocrine resistance, the role of proteoglycans in cancer, pancreatic cancer, acute myeloid leukemia, and infections caused by Kaposi sarcoma-associated herpesvirus.

3.6 Molecular docking findings

Utilizing Amoxicillin as a positive control, molecular docking was conducted between the initial five core compounds and the first five identified targets, with the subsequent calculation of binding energy. Binding energies below zero indicated the spontaneous binding capability of drug compounds to target proteins. Specifically, binding energies below −5 kcal/mol demonstrated substantial binding affinity, while those below −7.0 kcal/mol indicated strong binding capacity [16]. Molecular docking results (Fig 7) revealed that key compounds and targets could spontaneously bind, with 21 pairs exhibiting binding energies below −5 kcal/mol and 5 pairs below −7.0 kcal/mol. Specially, Inoleic acid and Syringolin A exhibit stronger binding affinities to AKT1, CASP3, EGFR, IL6, and STAT3 compared to the positive control Amoxicillin.

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Fig 7. Heat map illustrating the binding energies between EERM compounds and their targets.

https://doi.org/10.1371/journal.pone.0313743.g007

Visual analysis of the targets with the highest binding affinities to the core compounds was conducted, as presented in Fig 8. Notably, 4-hydroxy-2-O-methylanigorufone formed a hydrogen bond with STAT3 at GLU A:62, resulting in a binding energy of −6.63 kcal/mol, indicative of strong binding affinity. Similarly, 7β-hydroxyrutaecarpine and STAT3 formed a hydrogen bond at GLN A:96, with a binding energy of −6.52 kcal/mol, suggesting strong binding capacity. Hydroxyanigorufone interacted with STAT3 through hydrogen bonds at ASP A:97 and ASP A:158, with a binding energy of −6.69 kcal/mol, indicating strong binding affinity. Linoleic acid formed a hydrogen bond with STAT3 at GLN A:96, leading to a binding energy of −7.46 kcal/mol, showing very strong binding affinity. Lastly, Syringolin A formed hydrogen bonds with STAT3 at LYS A:105, ASP A:102, and ALA A:26, with a binding energy of −8.87 kcal/mol, demonstrating a highly strong binding affinity.

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Fig 8. Molecular docking diagrams.

(A) 4-hydroxy-2-O-methylanigorufone and STAT3; (B) 7β-hydroxyrutaecarpine and STAT3; (C) hydroxyanigorufone and STAT3; (D) linoleic acid and STAT3; (E) Syringolin A and STAT3.

https://doi.org/10.1371/journal.pone.0313743.g008

3.7 Molecular dynamics simulation

This study performed a 50 ns MD simulation analysis on the Syringolin A interactions with AKT1, CASP3, EGFR, IL6, and STAT3 complex systems, based on the molecular docking results. Root mean square deviation (RMSD) is used to assess the fluctuation index of protein conformation. A smaller RMSD value indicates a higher similarity between two structures [17]. The stability of the four Syringolin A complexes with AKT1, CASP3, IL6, and STAT3 gradually improved after 10 ns, as depicted in Fig 9A. However, the RMSD curve for the Syringolin A-EGFR complex fluctuated between 0.35 nm and 0.75 nm at 34 ns, suggesting insufficient stability in the complex conformation. Fig 9B and 9C show that in all simulated systems, the Solvent Accessible Surface Area (SASA) and Radius of Gyration (Rg) remained relatively stable, indicating a close interaction between Syringolin A and the key target. The analysis presented in Fig 9D illustrates the varying number of hydrogen bonds in the Syringolin A-AKT1, Syringolin A-CASP3, Syringolin A-EGFR, Syringolin A-IL6, and Syringolin A-STAT3 complexes over a 50 ns simulation period. The number of hydrogen bonds ranged from 1 to 6 in these complexes, with values of 4–10, 1–4, 3–8, and 1–4 observed for Syringolin A-AKT1, Syringolin A-CASP3, Syringolin A-EGFR, and Syringolin A-STAT3, respectively. Notably, the Syringolin A-CASP3 and Syringolin A-IL6 complexes exhibited a higher propensity to form hydrogen bonds throughout the simulation.

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Fig 9. The MD simulation of Syringolin A with AKT1, CASP3, EGFR, IL6, and STAT3 complex systems.

(A) RMSD curve. (B) SASA curve. (C) Rg curve. (D) H-bonds number.

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The Gibbs energy landscape of five groups of complexes is illustrated in Fig 10. Within this landscape, there are two distinct energy clusters present in the Gibbs energy 3D topography of the Syringolin A-AKT1, Syringolin A-EGFR, Syringolin A-IL6, and Syringolin A-STAT3 complexes. Conversely, the Gibbs energy 3D topography of the Syringolin A-CASP3 complex displays a single and smooth energy cluster. These findings indicate that all five groups of complexes exhibit the ability to spontaneously combine and possess relatively stable binding capabilities, with the Syringolin A-CASP3 complex demonstrating the strongest binding ability.

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Fig 10. Gibbs energy analysis of five groups of complexes.

(A) Syringolin A-AKT1 complex. (B) Syringolin A-CASP3 complex. (C) Syringolin A-EGFR complex. (D) Syringolin A-IL6 complex. (E) Syringolin A-STAT3 complex.

https://doi.org/10.1371/journal.pone.0313743.g010

The final 20 ns stable RMSD trajectory was calculated using the analysis of protein ligand Molecular Mechanics Generalized Born Surface Area method (MM/PBSA) to determine the complex binding free energy. Table 5 displays the total binding free energy values for different complexes: -17.55 kJ/mol for Syringolin A-AKT1, -38.98 kJ/mol for Syringolin A-CASP3, -17.55 kJ/mol for Syringolin A-EGFR, -21.42 kJ/mol for Syringolin A-IL6, and -31.71 kJ/mol for Syringolin A-STAT3. The results align with the molecular docking findings, showing that all five groups of complexes are capable of binding spontaneously.

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Table 5. Binding free energy and energy compounds calculated by MM/PBSA (KJ/mol).

https://doi.org/10.1371/journal.pone.0313743.t005

3.8 EERM promotes the proliferation of hFOB1.19 cells

After 48 hours of treatment with EERM, the proliferation rate of hFOB1.19 cells varied according to the concentration of EERM (Fig 11). Treatment with 60 μg/mL EERM resulted in the highest proliferation rate of hFOB1.19 cells, which was significantly greater than that of the control group (p < 0.05).

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Fig 11. EERM promotes the proliferation of hFOB1.19 cells (x ± s, n = 6).

* represents p < 0.05.

https://doi.org/10.1371/journal.pone.0313743.g011

3.9 EERM regulates the expression of related genes

The expression of related genes in hFOB1.19 cells was analyzed using qPCR technology. Treatment with 60 μg/mL EERM for 48 hours significantly altered the expression levels of these genes (Fig 12). Specifically, EERM markedly up-regulated the expression of EGFR, IL-6, and STAT3, while down-regulating the expression of AKT1 and CASP3.

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Fig 12. RM decoction regulates the related genes expression in hFOB1.19 cells.

(x ± s, n = 9). * represents p < 0.05, ** represents p < 0.01, *** represents p < 0.001.

https://doi.org/10.1371/journal.pone.0313743.g012

4. Discussion

Rhizoma Musae, a traditional medicine from the Miao ethnic region in Guizhou Province, China, is recognized for its heat-clearing and detoxifying properties [18]. The role and mechanism of Rhizoma Musae in treating fractures are not fully understood. In this study, UHPLC-Q-Exactive-MS/MS technology was used to identify 522 chemical compounds in EERM, with a focus on flavonoids, prenol lipids, and organooxygen compounds. A detailed component-target correlation analysis of the 70 most abundant compounds revealed key compounds effective for fracture treatment.

Hydroxy-2-O-methylanigorufone, a phytoalexin extracted from Musa spp. (Baxijiao) flowers [19], exhibits a notable α-glucosidase inhibitory effect. Syringolin A, produced by the plant pathogen Pseudomonas syringae pv. syringae, inhibits proteasomal activity in multiple myeloma [20]. Additionally, 7β-hydroxyrutaecarpine, derived from evodiacarpine, is an indopyridine-quinazoline alkaloid that undergoes hydroxylation and was initially detected in the callus tissue of Phellodendron [21]. Evodiacarpine is known for its analgesic, anti-inflammatory, and anti-diarrheal pharmacological effects [22]. Linoleic acids, polyunsaturated fatty acids commonly found in the human diet [23], are associated with reduced risks of atherosclerosis, hypertension, and diabetes [24], enhanced immune function [25], and improved musculoskeletal health [26]. Hydroxyanigorufone, a natural compound from banana fruit, plays a key role in phytoalexin synthesis [27].

Network pharmacology, which examines interactions between biomolecules and targets through drug structure and effect similarities [28], provides a comprehensive approach to understanding the mechanisms of TCM and their formulations. This methodology offers new insights into the interaction networks of TCMs in treating complex diseases [29]. The PPI network analysis for fracture treatment using EERM identified 59 key targets, including AKT1, IL-6, EGFR, STAT3, and CASP3. AKT1, encoded by the PKB gene and belonging to the AKT serine/threonine kinase family, plays a crucial role in the PI3K signaling pathway. It affects downstream effectors that are key in abnormal bone cell proliferation, synovial inflammation, as well as osteoclast formation and differentiation [30]. IL-6, a multifunctional cytokine, impacts the immune and nervous systems and is linked to antimicrobial molecule production and cytokine activity [31]. EGFR, a member of the ERBB family of tyrosine kinase receptors, regulates cellular processes such as proliferation, differentiation, division, survival, and oncogenesis [32]. STAT3, part of the STAT family, governs cell growth, differentiation, survival, anti-inflammatory activity, tissue repair, and cancer development [33]. CASP3, from the caspase family of cysteine-dependent aspartate-directed proteases, plays a pivotal role in programmed cell death mechanisms [34] like apoptosis and pyroptosis, crucial in inflammatory diseases [35]. In vitro cell experiments demonstrated that EERM enhanced cell proliferation by upregulating EGFR and STAT3 while downregulating the expression levels of AKT1 and CASP3. These findings are consistent with the gene functions reported in the aforementioned literature.

GO analysis on 279 potential targets revealed associations with various CCs, such as membrane rafts, membrane microdomains, and neuronal cell bodies, all crucial for fracture healing [36]. These findings suggest that these targets could serve as potential therapeutic targets. Additionally, these targets are involved in multiple MFs such as protein serine/threonine kinase activity, protein serine kinase activity, and nuclear receptor activity, affecting BPs like peptidyl-serine phosphorylation, response to xenobiotic stimulus, and nutrient levels. Therefore, EERM’s therapeutic effects on fractures result from the combined action of multiple biological processes.

The KEGG pathway enrichment analysis highlighted 20 key signaling pathways significantly influenced by EERM, including the PI3K-Akt signaling pathway, lipid metabolism and atherosclerosis, and EGFR TKI resistance. The PI3K-AKT pathway, critical for processes such as proliferation, differentiation, invasion, and apoptosis [37], was underscored with 50 core gene targets including GSK3B, IGF1R, and INSR. The analysis also identified inflammation-related targets within lipid and atherosclerosis pathways, such as STAT3, MMP9, MMP1, and AKT1, emphasizing the role of chronic inflammation in atherosclerosis development [38]. EGFR, a transmembrane tyrosine kinase that interacts with EGF family ligands, activates downstream pathways like MAPK, enhancing DNA synthesis and cellular proliferation [39]. TKIs, which inhibit tyrosine kinase phosphorylation and activation, are used in cancer treatment despite common resistance issues [40]. The MAPK pathway, involving JNK, ERK, and p38, is essential for apoptosis, differentiation, and proliferation, primarily through the activation of transcription factors [41]. This approach leverages interconnected, cooperative, and multi-level regulation. EERM achieves therapeutic effects on fractures by targeting key elements, regulating the entire signaling network, and influencing bone cell proliferation and differentiation. However, this research still has some limitations. Additional pharmacological experiments as well as in vitro and in vivo experiments are needed to validate the key targets and associated signaling pathways identified through network pharmacology analysis.

5. Conclusion

This study, leveraging UHPLC-Q-Exactive-MS/MS technology and network pharmacology, identified the potential therapeutic effects of EERM on fractures. Molecular docking was employed to simulate and confirm the interactions between key compounds and targets, elucidating the pharmacological basis, critical targets, and pathways involved in treating fractures with EERM. A total of 522 compounds were detected in EERM, with compounds such as 4′-hydroxy-2-O-methylanigorufone, Syringolin A, 7β-hydroxyrutaecarpine, linoleic acid, and hydroxyanigorufone highlighted for their fracture treatment potential. Network pharmacology analysis identified essential targets, including AKT1, IL-6, EGFR, STAT3, and CASP3. EERM promotes cell proliferation by upregulating the expression levels of EGFR and STAT3, while downregulating AKT1 and CASP3. These targets may enhance bone cell proliferation through various potential influencing pathways, including the PI3K-Akt signaling pathway, lipid metabolism and atherosclerosis, EGFR TKI resistance, and the MAPK signaling pathway.

Supporting information

S1 Table. A total of 522 compounds in ethanol extracts from Rhizoma Musae.

https://doi.org/10.1371/journal.pone.0313743.s001

(DOCX)

S2 Table. Analysis of the topological parameters of the core targets.

https://doi.org/10.1371/journal.pone.0313743.s002

(DOCX)

Acknowledgments

We extend our gratitude to Bullet Edits Limited for their linguistic editing and proofreading of the manuscript.

References

  1. 1. Guizhou Medical Products Administration. Quality standards of traditional Chinese medicine and ethnic medicine in Guizhou Province. 366 (Guiyang China: Guizhou Science and Technology Press, 2003).
  2. 2. Qian HB, Sun YC, Huang J, Wang XP. Experimental Study on Anti-inflammatory and Analgesic Effects of Different Extracts from Musa basjoo. Lishizhen Medicine and Materia Medica Research. 2010; 21: 780–781.
  3. 3. Palanisamy P, Alam M, Li S, Chow SKH, Zheng YP. Low-Intensity Pulsed Ultrasound Stimulation for Bone Fractures Healing: A Review. J Ultrasound Med. 2022;41(3):547–563. pmid:33949710
  4. 4. Bigham-Sadegh A, Oryan A. Basic concepts regarding fracture healing and the current options and future directions in managing bone fractures. Int Wound J. 2015;12(3):238–247. pmid:24618334
  5. 5. Liu HF, Meng DF, Yu P, De JC, Li HY. Obesity and risk of fracture in postmenopausal women: a meta-analysis of cohort studies. Ann Med. 2023;55(1):2203515. pmid:37190975
  6. 6. Ren X, Zhu Y, Xie L, Zhang M, Gao L, He H. Yunnan Baiyao diminishes lipopolysaccharide-induced inflammation in osteoclasts. J Food Biochem. 2020;44(6):e13182. pmid:32189353
  7. 7. Wang L, You X, Lotinun S, Zhang L, Wu N, Zou W. Mechanical sensing protein PIEZO1 regulates bone homeostasis via osteoblast-osteoclast crosstalk. Nat Commun. 2020;11(1):282. Published 2020 Jan 15. pmid:31941964
  8. 8. Hu K, Olsen BR. Osteoblast-derived VEGF regulates osteoblast differentiation and bone formation during bone repair. J Clin Invest. 2016;126(2):509–526. pmid:26731472
  9. 9. Deng M, Chen H, Long J, Song J, Xie L, Li X. Calycosin: a Review of its Pharmacological Effects and Application Prospects. Expert Rev Anti Infect Ther. 2021;19(7):911–925. pmid:33346681
  10. 10. Wang C, Dai S, Gong L, Fu K, Ma C, Liu YF, et al. A Review of Pharmacology, Toxicity and Pharmacokinetics of 2,3,5,4’-Tetrahydroxystilbene-2-O-β-D-Glucoside. Front Pharmacol. 2022;12:791214. Published 2022 Jan 5. pmid:35069206
  11. 11. Ma X, Yang J, Liu T, Li J, Lan YY, Wang YL, et al. Gukang Capsule Promotes Fracture Healing by Activating BMP/SMAD and Wnt/β-Catenin Signaling Pathways. Evid Based Complement Alternat Med. 2020;2020:7184502. Published 2020 Sep 29. pmid:33062020
  12. 12. Dong L, Xu M, Chen HJ, Guo T, Dong YX. Screening of Effective Components of Banana Root Promoting Osteoblast Proliferation and Differentiation. China & Foreign Medical Treatment. 2019; 38: 13–16.
  13. 13. Zhao L, Zhang H, Li N, Chen JM, Xu H, Wang YJ, et al. Network pharmacology, a promising approach to reveal the pharmacology mechanism of Chinese medicine formula. J Ethnopharmacol. 2023;309:116306. pmid:36858276
  14. 14. Hsin KY, Ghosh S, Kitano H. Combining machine learning systems and multiple docking simulation packages to improve docking prediction reliability for network pharmacology. PLoS One. 2013;8(12):e83922. Published 2013 Dec 31. pmid:24391846
  15. 15. Zhang D, Wang Z, Li J, Zhu J. Exploring the possible molecular targeting mechanism of Saussurea involucrata in the treatment of COVID-19 based on bioinformatics and network pharmacology. Comput Biol Med. 2022;146:105549. pmid:35751193
  16. 16. Nogales C, Mamdouh ZM, List M, Kiel C, Casas AI, Schmidt HHHW. Network pharmacology: curing causal mechanisms instead of treating symptoms. Trends Pharmacol Sci. 2022;43(2):136–150.
  17. 17. BRÜSCHWEILER R. Efficient RMSD measures for the comparison of two molecular ensembles. Root-mean-square deviation[J/OL]. Proteins. 2003; 50(1): 26–34. pmid:12471596
  18. 18. Li SZ, Compendium of Materia Medica. 30 (Chifeng China: Inner Mongolia Science and Technology Press, 2004).
  19. 19. Sheng Z, Dai H, Pan S, Wang H, Hu Y, Ma W. Isolation and characterization of an α-glucosidase inhibitor from Musa spp. (Baxijiao) flowers. Molecules. 2014;19(7):10563–10573. Published 2014 Jul 18. pmid:25045894
  20. 20. Opoku-Ansah J, Ibarra-Rivera TR, Pirrung MC, Bachmann AS. Syringolin B-inspired proteasome inhibitor analogue TIR-203 exhibits enhanced biological activity in multiple myeloma and neuroblastoma. Pharm Biol. 2012;50:25–29. pmid:22196580
  21. 21. Ikuta A, Urabe H, Nakamura T. A new indolopyridoquinazoline-type alkaloid from phellodendron amurense callus tissues. J Nat Prod. 1998;61:1012–1014. pmid:9722486
  22. 22. Hu X, Li D, Chu C, et al. Antiproliferative Effects of Alkaloid Evodiamine and Its Derivatives. Int J Mol Sci. 2018;19:3403. Published 2018 Oct 30. pmid:30380774
  23. 23. Ramsden CE, Ringel A, Feldstein AE, Taha AY, MacIntosh BA, Hibbeln JR, et al. Lowering dietary linoleic acid reduces bioactive oxidized linoleic acid metabolites in humans. Prostaglandins Leukot Essent Fatty Acids. 2012;87:135–141. pmid:22959954
  24. 24. Tricon S, Yaqoob P. Conjugated linoleic acid and human health: a critical evaluation of the evidence. Curr Opin Clin Nutr Metab Care. 2006;9:105–110. pmid:16477173
  25. 25. Zhang H, Guo Y, Yuan J. Conjugated linoleic acid enhanced the immune function in broiler chicks. Br J Nutr. 2005;94:746–752. pmid:16277778
  26. 26. Kim JH, Kim Y, Kim YJ, Park Y. Conjugated Linoleic Acid: Potential Health Benefits as a Functional Food Ingredient. Annu Rev Food Sci Technol. 2016;7:221–244. pmid:26735796
  27. 27. Kamo T, Hirai N, Tsuda M, Fujioka D, Ohigashi H. Changes in the content and biosynthesis of phytoalexins in banana fruit. Biosci Biotechnol Biochem. 2000;64(10):2089–2098. pmid:11129580
  28. 28. Li X, Liu Z, Liao J, Chen Q, Lu X, Fan X. Network pharmacology approaches for research of Traditional Chinese Medicines. Chin J Nat Med. 2023;21:323–332. pmid:37245871
  29. 29. Xu F, Wu H, Wang Y, Yang Y, Gao Y, Wang X. Determination of lupenone and β-sitosterol in Rhizoma Musae by UPLC with DAD and ELSD. J Chromatogr Sci. 2015;53(10):1714–1719. pmid:26126840
  30. 30. Hayer S, Pundt N, Peters MA, Wunrau C, Kühnel I, Neugebauer K, et al. PI3Kgamma regulates cartilage damage in chronic inflammatory arthritis. FASEB J. 2009;23:4288–4298. pmid:19734303
  31. 31. Rose-John S. IL-6 trans-signaling via the soluble IL-6 receptor: importance for the pro-inflammatory activities of IL-6. Int J Biol Sci. 2012;8:1237–1247. pmid:23136552
  32. 32. Sabbah DA, Hajjo R, Sweidan K. Review on Epidermal Growth Factor Receptor (EGFR) Structure, Signaling Pathways, Interactions, and Recent Updates of EGFR Inhibitors. Curr Top Med Chem. 2020;20:815–834. pmid:32124699
  33. 33. Liu Y, Liao S, Bennett S, Tang HJ, Song DZ, Wood D, et al. STAT3 and its targeting inhibitors in osteosarcoma. Cell Prolif. 2021;54:e12974. pmid:33382511
  34. 34. Kesavardhana S, Malireddi RKS, Kanneganti TD. Caspases in Cell Death, Inflammation, and Pyroptosis. Annu Rev Immunol. 2020;38:567–595. pmid:32017655
  35. 35. McIlwain DR, Berger T, Mak TW. Caspase functions in cell death and disease. Cold Spring Harb Perspect Biol. 2015;7:a026716. Published 2015 Apr 1. pmid:25833847
  36. 36. Hryniewicz-Jankowska A, Augoff K, Sikorski AF. The role of cholesterol and cholesterol-driven membrane raft domains in prostate cancer. Exp Biol Med (Maywood). 2019;244:1053–1061. pmid:31573840
  37. 37. Ma P, Gu B, Xiong W, Tan BS, Geng W, Li J, et al. Glimepiride promotes osteogenic differentiation in rat osteoblasts via the PI3K/Akt/eNOS pathway in a high glucose microenvironment. PLoS One. 2014;9:e112243. Published 2014 Nov 12.
  38. 38. Poznyak A, Grechko AV, Poggio P, Myasoedova VA, Alfieri V, Orekhov AN. The Diabetes Mellitus-Atherosclerosis Connection: The Role of Lipid and Glucose Metabolism and Chronic Inflammation. Int J Mol Sci. 2020;21:1835. Published 2020 Mar 6. pmid:32155866
  39. 39. Huang L, Fu L. Mechanisms of resistance to EGFR tyrosine kinase inhibitors. Acta Pharmaceutica Sinica. 2015; B, 5, 390–401. pmid:26579470
  40. 40. de Miguel FJ, Gentile C, Feng WW, Silva SJ, Silva A, Exposito F, et al. Mammalian SWI/SNF chromatin remodeling complexes promote tyrosine kinase inhibitor resistance in EGFR-mutant lung cancer. Cancer Cell. 2023;41:1516–1534.e9. pmid:37541244
  41. 41. Zheng W, Gu X, Hu D, Hao Y. Co-culture with synovial tissue in patients with rheumatoid arthritis suppress cell proliferation by regulating MAPK pathway in osteoblasts. Am J Transl Res. 2019;11:3317–3327. Published 2019 Jun 15. pmid:31312346