Astragalus Polysaccharide Inhibits Ionizing Radiation-Induced Bystander Effects by Regulating MAPK/NF-kB Signaling Pathway in Bone Mesenchymal Stem Cells (BMSCs)

Vanillic acid inhibits TGF-β type I receptor to protect bone marrow mesenchymal stem cells from radiation-induced bystander effects

Background

Radiotherapy is a major treatment option for non-small cell lung cancer (NSCLC); however, irradiated tumor cells can damage non-irradiated cells through radiation-induced bystander effects (RIBE), which can affect the therapeutic efficacy. The study aimed to investigate the mechanism underlying RIBE and the protective effects of vanillic acid (VA) on human bone marrow mesenchymal stem cells (BMSCs).

Methods

We established two irradiation models to investigate RIBE. First, we established the A549 cell irradiation model alone, and tested the expression of cathepsin B (CTSB) and transforming growth factor-beta 1 (TGF-β1) by western blot and immunofluorescence staining. Next, we established a co-culture model of A549 cells and BMSCs. After 2 Gy X-rays irradiation of A549 cells, BMSCs cell viability was detected using Cell Counting Kit-8 (CCK-8), reactive oxygen species (ROS) level was detected using flow cytometry, and CTSB, TGF-β type I receptor (TGFβRI), p62 (sequestosome 1), BECLIN1, microtubule-associated protein light chain 3 (LC3), etc., were detected using western blot. Phosphorylated histone H2AX (γH2AX), CTSB, lysosomal-associated membrane protein 1 (LAMP1), and TGFβRI expression levels were detected by immunofluorescence staining. Molecular docking and molecular dynamics simulation, and a CCK-8 assay were used to screen for molecules from Astragalus membranceus that inhibited TGFβRI activity, to protect BMSCs from RIBE. Lastly, we validated VA activity in vivo.

Results

In this study, 2 Gy X-rays radiation on A549 cells was found to result in an increase in CTSB and TGF-β1, while CTSB inhibitor CA074Me reduced the radiation-induced TGF-β1 increase. In the co-culture model of A549 cells and BMSCs, 2 Gy X-rays radiation on A549 cells resulted in increase of TGFβRI expression in BMSCs, which led to an increase in ROS, and resulted in DNA damage and the inhibition of BMSCs proliferation. The small molecule VA from Astragalus membranaceus inhibited TGFβRI activity and restored the proliferation of BMSCs.

Conclusions

Our findings reveal that radiation causes CTSB overexpression in A549 cells, which further promotes TGF-β1 expression. TGF-β1 activates its receptors on BMSCs to increase ROS levels in BMSCs, while reducing lysosomal double-chain CTSB (dc-CTSB), which results in decreased BMSCs autophagy and an inability to clear ROS, and thus inhibits proliferation. VA inhibits TGFβRI to restore the proliferation of BMSCs, and in vivo, VA can enhance the killing effect of radiation on tumors.

AOP Report: Development of an adverse outcome pathway for deposition of energy leading to bone loss

Bone loss, commonly seen in osteoporosis, is a condition that entails a progressive decline of bone mineral density and microarchitecture, often seen in post-menopausal women. Bone loss has also been widely reported in astronauts exposed to a plethora of stressors and in patients with osteoporosis following radiotherapy for cancer. Studies on mechanisms are well documented but the causal connectivity of events to bone loss development remains incompletely understood. Herein, the adverse outcome pathway (AOP) framework was used to organize data and develop a qualitative AOP beginning from deposition of energy (the molecular initiating event) to bone loss (the adverse outcome). This qualitative AOP was developed in collaboration with bone loss research experts to aggregate relevant findings, supporting ongoing efforts to understand and mitigate human system risks associated with radiation exposures. A literature review was conducted to compile and evaluate the state of knowledge based on the modified Bradford Hill criteria. Following review of 2029 studies, an empirically supported AOP was developed, showing the progression to bone loss through many factors affecting the activities of bone-forming osteoblasts and bone-resorbing osteoclasts. The structural, functional, and quantitative basis of each proposed relationship was defined, for inference of causal changes between key events. Current knowledge and its gaps relating to dose-, time- and incidence-concordance across the key events were identified, as well as modulating factors that influence linkages. The new priorities for research informed by the AOP highlight areas for improvement to enable development of a quantitative AOP used to support risk assessment strategies for space travel or cancer radiotherapy.

Natural small molecules synergize mesenchymal stem cells for injury repair in vital organs: a comprehensive review

Mesenchymal stem cells (MSCs) therapy is a highly researched treatment that has the potential to promote immunomodulation and anti-inflammatory, anti-apoptotic, and antimicrobial activities. It is thought that it can enhance internal organ function, reverse tissue remodeling, and achieve significant organ repair and regeneration. However, the limited infusion, survival, and engraftment of transplanted MSCs diminish the effectiveness of MSCs-based therapy. Consequently, various preconditioning methods have emerged as strategies for enhancing the therapeutic effects of MSCs and achieving better clinical outcomes. In particular, the use of natural small molecule compounds (NSMs) as a pretreatment strategy is discussed in this narrative review, with a focus on their roles in regulating MSCs for injury repair in vital internal organs. Additionally, the discussion focuses on the future directions and challenges of transforming mesenchymal stem cell research into clinical applications.

Abscopal Effects, Clastogenic Effects and Bystander Effects: 70 Years of Non-Targeted Effects of Radiation

In vitro and in vivo observations accumulated over several decades have firmly shown that the biological effects of ionizing radiation can spread from irradiated cells/tissues to non-targeted cells/tissues. Redox-modulated intercellular communication mechanisms that include a role for secreted factors and gap junctions, can mediate these non-targeted effects. Clearly, the expression of such effects and their transmission to progeny cells has implications for issues related to radiation protection. Their elucidation is also relevant towards enhancing the efficacy of cancer radiotherapy and reducing its impact on the development of normal tissue toxicities. In addition, the study of non-targeted effects is pertinent to our basic understanding of intercellular communications under conditions of oxidative stress. This review will trace the history of non-targeted effects of radiation starting with early reports of abscopal effects which described radiation induced effects in tissues distant from the site of radiation exposure. A related effect involved the production of clastogenic factors in plasma following irradiation which can induce chromosome damage in unirradiated cells. Despite these early reports suggesting non-targeted effects of radiation, the classical paradigm that a direct deposition of energy in the nucleus was required still dominated. This paradigm was challenged by papers describing radiation induced bystander effects. This review will cover mechanisms of radiation-induced bystander effects and the potential impacts on radiation protection and radiation therapy.

Ononin promotes radiosensitivity in lung cancer by inhibiting HIF-1α/VEGF pathway

BACKGROUND

In our previous study, we provided evidence that Astragalus mongholicus Bunge(AM) and its extracts possess a protective capability against radiation-induced damage, potentially mediated through the reduction of reactive oxygen species (ROS) and nitric oxide (NO). However, we were pleasantly surprised to discover during our experimentation that AM not only offers protection against radiation damage but also exhibits a radiation sensitization effect. This effect may be attributed to a specific small molecule present in AM known as ononin. Currently, radiation sensitizers are predominantly found in nitrazole drugs and nanomaterials, with no existing reports on the radiation sensitization properties of ononin, nor its underlying mechanism.

PURPOSE

This study aims to investigate the sensitization effect of the small molecule ononin derived from AM on lung cancer radiotherapy, elucidating its specific molecular mechanism of action. Additionally, the safety profile of combining astragalus small molecule ononin with radiation therapy will be evaluated.

METHODS

The effective concentration of ononin was determined through cell survival experiments, and the impact of ononin combined with varying doses of radiation on lung cancer cells was observed using CCK-8 and cell cloning experiments. The apoptotic effect of ononin combined with radiation on lung cancer cells was assessed using Hochester staining, flow cytometry, and WB assay. Additionally, WB and immunofluorescence analysis were conducted to investigate the influence of ononin on HIF-1α/VEGF pathway. Furthermore, Molecular Dynamics Simulation was employed to validate the targeted binding ability of ononin and HIF-1α. A lung cancer cell line was established to investigate the effects of knockdown and overexpression of HIF-1α. Subsequently, the experiment was repeated using tumor bearing nude mice and C57BL/6 mouse models in an in vivo study. Tumor volume was measured using a vernier caliper, while HE, immunohistochemistry, and immunofluorescence techniques were employed to observe the effects of ononin combined with radiation on tumor morphology, proliferation, and apoptosis. Additionally, Immunofluorescence was employed to examine the impact of ononin on HIF-1α/VEGF pathway in vivo, and its effect on liver function in mice was assessed through biochemistry analysis.

RESULTS

At a concentration of 25 μM, ononin did not affect the proliferation of lung epithelial cells but inhibited the survival of lung cancer cells. In vitro experiments demonstrated that the combination of ononin and radiation could effectively inhibit the growth of lung cancer cells, induce apoptosis, and suppress the excessive activation of the Hypoxia inducible factor 1 alpha/Vascular endothelial growth factor pathway. In vivo experiments showed that the combination of ononin and radiation reduced the size and proliferation of lung cancer tumors, promoted cancer cell apoptosis, mitigated abnormal activation of the Hypoxia inducible factor 1 alpha pathway, and protected against liver function damage.

CONCLUSION

This study provides evidence that the combination of AM and its small molecule ononin can enhance the sensitivity of lung cancer to radiation. Additionally, it has been observed that this combination can specifically target HIF-1α and exert its effects. Notably, ononin exhibits the unique ability to protect liver function from damage while simultaneously enhancing the tumor-killing effects of radiation, thereby demonstrating a synergistic and detoxifying role in tumor radiotherapy. These findings contribute to the establishment of a solid basis for the development of novel radiation sensitizers derived from traditional Chinese medicine.

Astragaloside IV protects LO2 cells from oxidative damage caused by radiation-induced bystander effect through Akt/Nrf2 pathway

Background

The protective effects of astragaloside IV (ASIV) on various diseases are well known, but its potential impact on radiation-induced bystander effect (RIBE) has remained unclear.

Objective

This study aimed to explore the protective mechanism of ASIV against oxidative damage caused by RIBE in LO2 cells.

Methods

To construct the RIBE model, the conditioned medium from HepG2 cells irradiated with radiation was transferred to nonirradiated LO2 cells. LY294002, a commonly used phosphatidylinositol 3-kinase/Akt pathway inhibitor, was added to LO2 cells 1 h before exposing HepG2 cells to radiation. LO2 cells were then collected for analyses after RIBE exposure.

Results

The study found that ASIV significantly improved cell proliferation and promoted the recovery of mitochondrial membrane potential while reducing the rate of apoptosis. Western blot analyses demonstrated that ASIV upregulated B-cell lymphoma 2 and downregulated B-cell lymphoma 2-related X protein and cleaved-caspase 3. Measurement of reactive oxygen species, superoxide dismutase, glutathione peroxidase, and malondialdehyde levels showed that ASIV effectively restored the oxidative stress state induced by RIBE. Additionally, immunofluorescence and western blots analyses confirmed that ASIV enhanced the translocation of Nrf2 to the nucleus and activated downstream nicotinamide adenine dinucleotide phosphate: quinine oxidoreductase 1 and heme oxygenase 1. Importantly, Akt pathway inhibitor repressed ASIV-induced activation of Nrf2 and its protective effect against RIBE.

Conclusion

This study demonstrates that ASIV protects LO2 cells against oxidative damage caused by RIBE through activation of the Akt/Nrf2 pathway.

Review: Mechanisms and perspective treatment of radioresistance in non-small cell lung cancer

Radiotherapy is the major treatment of non-small cell lung cancer (NSCLC). The radioresistance and toxicity are the main obstacles that leading to therapeutic failure and poor prognosis. Oncogenic mutation, cancer stem cells (CSCs), tumor hypoxia, DNA damage repair, epithelial-mesenchymal transition (EMT), and tumor microenvironment (TME) may dominate the occurrence of radioresistance at different stages of radiotherapy. Chemotherapy drugs, targeted drugs, and immune checkpoint inhibitors are combined with radiotherapy to treat NSCLC to improve the efficacy. This article reviews the potential mechanism of radioresistance in NSCLC, and discusses the current drug research to overcome radioresistance and the advantages of Traditional Chinese medicine (TCM) in improving the efficacy and reducing the toxicity of radiotherapy.

Research on the Mechanism of HRP Relieving IPEC-J2 Cells Immunological Stress Based on Transcriptome Sequencing Analysis

Early weaning increased the economic benefits of piglets. However, early weaning damages the intestinal barrier of piglets and causes immunological stress. The mechanism by which Hippophae rhamnoides polysaccharide (HRP) alleviates lipopolysaccharide (LPS)-induced intestinal porcine epithelial cells (IPEC-J2) inflammatory damage was investigated using proteomics in our previous studies. In this study we employed RNA-sequencing (RNA-seq) to determine the level and function of differentially expressed genes (DEGs) and further explore the mechanism of the HRP anti-inflammatory and immune process. The differential expression analysis indicated that 3622, 1216, and 2100 DEGs in the IPEC-J2 cells were identified in C vs. L, L vs. H6-L, and C vs. H6-L, respectively. The Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis foundsix identified pathways related to the immune system. Additionally, we used the Science, Technology, Engineering, and Math (STEM) program to categorize the 3,134 DEGs that were differentially expressed in H2-L, H4-L and H6-L into eight possible expression profiles, in which 612 were clustered into two profiles. The accuracy and consistency of RNA-seq data were validated by the results of qRT-PCR of the nuclear factor of kappa light polypeptide gene enhancer in B-cells 2 (NFKB2), MAP kinase interacting serine/threonine kinase 2 (MKNK2), mitogen-activated protein kinase kinase 1 (MAP2K1), mitogen-activated protein kinase kinase kinase 8 (MAP3K8), Ras-related protein R-Ras (RRAS), TNF receptor-associated factor 1 (TRAF1), NF-kappa-B inhibitor alpha (NFKBIA), interleukin 8 (IL8), tumor necrosis factor, alpha-induced protein 3 (TNFAIP3), and transforming growth factor beta-1 (TGFB1). Transcriptome sequencing also indicated that HRP reduced the expression levels of related DEGs and inhibited the activation of the mitogen-activated protein kinase (MAPK)/nuclear factor kappa-B (NF-κB) signaling pathway. Our findings indicate that the application of HRP in piglet diets during the early weaning period can improve intestinal epithelial function and integrity, and relieve intestinal damage, and improve piglet health.

Promoting reactive oxygen species generation: a key strategy in nanosensitizer-mediated radiotherapy

The radiotherapy enhancement effect of numerous nanosensitizers is based on the excessive production of reactive oxygen species (ROS), and only a few systematic reviews have focused on the key strategy in nanosensitizer-mediated radiotherapy. To clarify the mechanism underlying this effect, it is necessary to understand the role of ROS in radiosensitization before clinical application. Thus, the source of ROS and their principle of tumor inhibition are first introduced. Then, nanomaterial-mediated ROS generation in radiotherapy is reviewed. The double-edged sword effect of ROS and the potential dangers they may pose to cancer patients are subsequently addressed. Finally, future perspectives regarding ROS-regulated nanosensitizer applications and development are discussed.

Review of the Efficacy and Mechanisms of Traditional Chinese Medicines as a Therapeutic Option for Ionizing Radiation Induced Damage

Ionizing radiation damage refers to acute, delayed, or chronic tissue damage associated with ionizing radiation. Specific or effective therapeutic options for systemic injuries induced by ionizing radiation have not been developed. Studies have shown that Chinese herbal Medicine or Chinese Herbal Prescription exhibit preventive properties against radiation damage. These medicines inhibit tissue injuries and promote repair with very minimal side effects. This study reviews traditional Chinese herbal medicines and prescriptions with radiation protective effects as well as their mechanisms of action. The information obtained will guide the development of alternative radioprotectants.

External modulators and redox homeostasis: Scenario in radiation-induced bystander cells

Redox homeostasis is imperative to maintain normal physiologic and metabolic functions. Radiotherapy disturbs this balance and induces genomic instability in diseased cells. However, radiation-induced effects propagate beyond the targeted cells, affecting the adjacent non-targeted cells (bystander effects). The cellular impact of radiation, thus, encompasses both targeted and non-targeted effects. Use of external modulators along with radiation can increase radio-therapeutic efficiency. The modulators' classification as protectors or sensitizers depends on interactions with damaged DNA molecules. Thus, it is necessary to realize the functions of various radio-sensitizers or radio-protectors in both irradiated and bystander cells. This review focuses on some modulators of radiation-induced bystander effects (RIBE) and their action mechanisms. Knowledge about the underlying signaling cross-talk may promote selective sensitization of radiation-targeted cells and protection of bystander cells.

Astragalus polysaccharide inhibits radiation-induced bystander effects by regulating apoptosis in Bone Mesenchymal Stem Cells (BMSCs)

The purpose of this study was to investigate the effects of astragalus polysaccharides (APS) on the proliferation and apoptosis of bone marrow mesenchymal stem cells (BMSCs) induced by X-ray radiation-induced A549 cells bystander effect (RIBE), and to explore their mechanisms. In this study, APS increased the reduced cell proliferation rate induced by RIBE and inhibiting the apoptosis of bystander cells. In terms of mechanism, APS up-regulates the proteins Bcl-2, Bcl-xl, and down-regulates the proteins Bax and Bak, which induces a decrease in mitochondrial membrane potential, which induces the release of Cyt-c and AIF, which leads to caspase-dependent and caspase-independent pathway to cause apoptosis. In addition, we believe that ROS may be the main cause of these protein changes. APS can inhibit the generation of ROS in bystander cells and thus inhibit the activation of the mitochondrial pathway, further preventing cellular damage caused by RIBE.

Astragalus polysaccharides attenuate pulmonary fibrosis by inhibiting the epithelial-mesenchymal transition and NF-κB pathway activation

Astragalus polysaccharides (APS), the active ingredients isolated from the plant Astragalus, have been reported to have numerous biological activities, including anti‑inflammatory and antitumor activities. However, the effect of APS on pulmonary fibrosis (PF) remains unknown. The present study aimed to evaluate the protective effect of APS against PF and to explore its underlying mechanisms by using in vivo and in vitro models. A mouse in vivo model of bleomycin‑induced PF and an in vitro model of transforming growth factor β1 (TGF‑β1)‑stimulated human lung epithelial A549 cells were established. Histopathologic examination and collagen deposition were investigated by hematoxylin and eosin staining and Masson staining, and by detecting the hydroxyproline content. The expression of related genes was analyzed by western blotting, reverse transcription‑quantitative (RT‑q) PCR, immunofluorescence and immunohistochemistry. The results from the in vivo mouse model demonstrated that treatment with APS could ameliorate collagen deposition and reduce fibrotic area and hydroxyproline content in the matrix. Furthermore, APS significantly inhibited the epithelial‑mesenchymal transition (EMT), as evidenced by an increased level of E‑cadherin and a decreased expression of vimentin and alpha smooth muscle actin. Furthermore, APS treatment significantly decreased TGF‑β1‑induced EMT and NF‑κB pathway activation in vitro. The results from the present study provided new insights on PF regression via the anti‑fibrotic effects of APS.

A Chinese herbal prescription Yiqi Jiedu decoction attenuates irradiation induced testis injury in mice

OBJECTIVE

Yiqi Jiedu (YQJD) decoction is a Chinese herbal prescription, based on an experienced expert of traditional Chinese medicine. It is used for the injuries caused by radiotherapy. The current study was designed to investigate the protective effects of YQJD decoction on radiation damage of testis in mice, and to explore its potential mechanisms.

METHODS

Mice were randomly divided into blank control group (Ctrl), model group (IR), positive drug group (IRA), and YQJD decoction group (IRY). After 10-day period intervention, they were whole-body irradiated with 2 Gy ⁶⁰Co γ-rays and sacrificed on 7^th day after irradiation. The indicators including the index and histopathology examination of testis, spermatogenic cell types and apoptosis, and the expression of TLR5, MyD88, NF-κB, TNF-α, IL-6 and Bcl-2 in testis.

RESULTS

The testis atrophied significantly on 7^th day of exposure to radiation, while YQJD decoction promoted the recovery of testis index and structure. Moreover, spermatogenic cell types and apoptosis had significant changes after irradiation. YQJD decoction protected the testicular function of spermatogenesis, as while as reduced the apoptosis rate of spermatogenic cells. In addition, RT-PCR and immunohistochemical analysis showed that YQJD decoction up-regulated the expression of TLR5 in testis. The levels of TLR5's downstream factors were also up-regulated in YQJD decoction group, which indicated that TLR5 signaling pathway might play an important role in the protective effects of YQJD decoction.

CONCLUSIONS

The results showed that YQJD decoction attenuated irradiation induced testis injury in mice. Its potential mechanism was related to TLR5 signaling pathway.

The Effects of Astragalus Polysaccharide on Bone Marrow-Derived Mesenchymal Stem Cell Proliferation and Morphology Induced by A549 Lung Cancer Cells

BACKGROUND The tumor microenvironment in lung cancer plays an important role in tumor progression and metastasis. Bone marrow-derived mesenchymal stem cells (MSCs) co-cultured with A549 lung cancer cells show changes in morphology, increase cell proliferation, and cell migration. This study aimed to investigate the effects of Astragalus polysaccharide (APS), a traditional Chinese herbal medicine, on the changes induced in bone marrow-derived MSCs by A549 lung cancer cells in vitro. MATERIAL AND METHODS Bone marrow-derived MSCs were co-cultured with A549 cells (Co-BMSCs). Co-cultured bone marrow-derived MSCs and A549 cells treated with 50 μg/ml of APS (Co-BMSCs + APS) were compared with untreated Co-BMSCs. Cell proliferation was measured using the cell counting kit-8 (CCK-8) assay. Flow cytometry evaluated the cell cycle. Microarray assays for mRNA expression and Western blot for protein expression were used. RESULTS Compared with untreated Co-BMSCs, APS treatment of Co-BMSCs improved cell morphology, reduced cell proliferation, and inhibited cell cycle arrest. The mitogen-activated protein kinase (MAPK)/nuclear factor-kappa B (NF-kappaB) pathway, TP53, caspase-3, acetylated H4K5, acetylated H4K8, and acetylated H3K9 were involved in the regulatory process. CONCLUSIONS APS treatment reduced cell proliferation and morphological changes in bone marrow-derived MSCs that were co-cultured with A549 lung cancer cells in vitro.