Amifostine inhibited the differentiation of RAW264.7 cells into osteoclasts by reducing the production of ROS under 2 Gy radiation

Wogonin induces apoptosis in macrophages by exhibiting cytotoxic and genotoxic effects

Macrophages play an important role in defending the body against invading pathogens. In the face of pathogens, macrophages become activated and release toxic materials that disrupt the pathogens. Macrophage overactivation can lead to severe illness and inflammation. Wogonin has several therapeutic effects, including anti-inflammatory, anticancer, antioxidant, and neuroprotective effects. No studies have investigated the cytotoxic effects of wogonin at concentrations of more than 0.1 mM in RAW264.7 cells. In this study, RAW 264.7 cells were treated with wogonin, which, at concentrations of more than 0.1 mM, had cytotoxic and genotoxic effects in the RAW264.7 cells, leading to apoptosis and necrosis. Further, wogonin at concentrations of more than 0.1 mM induced caspase-3, caspase-8, and caspase-9 activation and mitochondrial dysfunction and death receptor expression. These results suggest that wogonin induces apoptosis through upstream intrinsic and extrinsic pathways by exhibiting cytotoxic and genotoxic effects.

Advances of Amifostine in Radiation Protection: Administration and Delivery

Amifostine (AMF, also known as WR-2721) is the only approved broad-spectrum small-molecule radiation protection agent that can combat hematopoietic damage caused by ionizing radiation and is used as an antitumor adjuvant and cell protector in cancer chemotherapy and radiotherapy. Amifostine is usually injected intravenously before chemotherapy or radiotherapy and has been used in the treatment of head and neck cancer. However, the inconvenient intravenous administration and its toxic side effects such as hypotension have severely limited its further application in clinic. In order to reduce the toxic and side effects, scientists are trying to develop a variety of drug administration methods and are devoted to developing a wide application of amifostine in radiation protection. This paper reviews the research progress of amifostine for radiation protection in recent years, discusses its mechanism of action, clinical application, and other aspects, with focus on summarizing the most widely studied amifostine injection administration and drug delivery systems, and explored the correlation between various administrations and drug efficacies.

Role of reactive oxygen species and mitochondrial damage in rheumatoid arthritis and targeted drugs

Rheumatoid arthritis (RA) is an autoimmune disease characterized by synovial inflammation, pannus formation, and bone and cartilage damage. It has a high disability rate. The hypoxic microenvironment of RA joints can cause reactive oxygen species (ROS) accumulation and mitochondrial damage, which not only affect the metabolic processes of immune cells and pathological changes in fibroblastic synovial cells but also upregulate the expression of several inflammatory pathways, ultimately promoting inflammation. Additionally, ROS and mitochondrial damage are involved in angiogenesis and bone destruction, thereby accelerating RA progression. In this review, we highlighted the effects of ROS accumulation and mitochondrial damage on inflammatory response, angiogenesis, bone and cartilage damage in RA. Additionally, we summarized therapies that target ROS or mitochondria to relieve RA symptoms and discuss the gaps in research and existing controversies, hoping to provide new ideas for research in this area and insights for targeted drug development in RA.

ROS-responsive resveratrol-loaded cyclodextrin nanomicelles reduce inflammatory osteolysis

Bone loss in inflammatory disorders such as osteomyelitis, septic arthritis, and periodontitis is caused by excessive osteoclastic activity. Meanwhile, reactive oxygen species (ROS) have been identified as contributors to osteoclast differentiation, and the application of ROS scavengers has emerged as a promising strategy to protect against bone loss. Recently, resveratrol (RSV), a polyphenolic phytoalexin, has been demonstrated to inhibit osteoclastogenesis by scavenging ROS; however, the application of RSV as an antioxidant is limited by its low water solubility, structural instability, and short elimination half-life. In this study, we developed a PEGylated cyclodextrin (CD)-based nanoplatform (PCP) for local delivery of RSV as nanomicelles (RSV-NMs). In addition, polymer functionalization with phenylboronic acid ester in RSV-NMs successfully achieved ROS-responsive release of RSV. The RSV-NMs in a well-dispersed state possessed good biocompatibility as well as improved solubility and stability compared with RSV compound. In vitro, RSV-NMs significantly inhibited the formation of tartrate-resistant acid phosphatase (TRAP)-positive multinuclear cells and suppressed F-actin (filamentous actin) ring formation. Additionally, the mRNA expressions of osteoclastic marker genes, including matrix metalloprotein-9 (MMP-9), nuclear factor of activated T cells 1 (NFATc1), TRAP, and cathepsin K, were consequently downregulated in the presence of RSV-NMs. In vivo, RSV-NMs provided protection against LPS-induced bone destruction, as evidenced by a decreased number of osteoclasts, increased bone density, and reduced area of bone resorption. Taken together, these results indicate that our ROS-responsive RSV-NMs can be employed as a potential therapeutic agent for the treatment of inflammatory osteolysis.

Effect of Yang He Decoction on Treatment of Bone Tuberculosis via Phosphoinositide 3-Kinases/Protein Kinase B and Mitogen-Activated Protein Kinase Signaling Pathways

Yang He Decoction (YHD), a classical Chinese medicine prescription, is used to treat bone and joint diseases. However, there are few mechanism studies for YHD on the use of YHD to treat bone tuberculosis (BT) and the corresponding mechanism of action of YHD. In the present study, the chemical ingredients of YHD and targets of the ingredients were revealed by a network pharmacology method, and an ingredient–target–disease network was visualized and analyzed. Then, gene ontology enrichment analysis and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis were carried out. In addition, molecular docking was performed to clarify the binding of the key active ingredients of YHD to the key targets. Further, an in vitro model of Mycobacterium tuberculosis-induced BT was established, and a mechanism for the inhibitory effect of YHD on the differentiation of RAW 264.7 cells into osteoclasts was investigated. A total of 138 active ingredients in YHD and 50 targets between YHD ingredients and BT were identified. The phosphatidylinositol 3-kinase–protein kinase B (PI3K–Akt) and mitogen-activated protein kinase (MAPK) signaling pathways were the key pathways involved in the anti-BT effect of YHD. Moreover, the in vitro results showed that YHD inhibited the differentiation of RAW 264.7 cells into osteoclasts. YHD decreased the levels of tumor necrosis factor-α and interleukin-1β, increased the levels of superoxide dismutase and glutathione peroxide, and decreased the level of malondialdehyde. Further, YHD inhibited the protein and messenger RNA expression of PI3K/Akt, p38 MAPK, and c-Jun N-terminal kinase. These findings show that YHD is a promising anti-BT agent that suppresses the PI3K/Akt and MAPK signaling pathways to inhibit the differentiation of RAW 264.7 cells into osteoclasts and ameliorate inflammation and oxidative stress.

The role of small GTPase Rac1 in ionizing radiation-induced testicular damage

PURPOSE

The main acute and late effects of ionizing radiation on living organisms are the formation of reactive oxygen species (ROS), apoptosis and DNA damage. Since the Rac1 molecule is a subunit of the NADPH oxidase enzyme, it is known to participate in the generation of ROS. The aim of this study was to investigate the role of Rac1 molecule in testicular damage induced by low (0.02 Gy), medium (0.1 Gy) and high (5 Gy) dose irradiation.

MATERIAL AND METHOD

In this study, Wistar rats (except the control group) were received whole body X-ray irradiation. Testicular tissues were removed 2 hours, 24 hours and 7 days after radiation exposure. Testicular damage was examined by hematoxylin-eosin staining and Johnsen's score. Immunohistochemical staining and G-LISA method were used to determine Rac1 expression and activation. To evaluate the generation of ROS in the testicular tissues, intracellular ROS, superoxide dismutase (SOD) and malondialdehyde (MDA) levels were measured.

RESULTS

Increases in testicular damage were detected in all radiation exposed groups in a dose- and time-dependent manner. Compared to the control group, Rac1 expression decreased in all irradiated groups, while Rac1 activation increased. In addition, intracellular ROS and MDA levels were increased and SOD activity levels decreased in the irradiated groups compared to the control group.

CONCLUSION

Our findings suggest that Rac1 has a role in the increase of intracellular ROS and lipid peroxidation which led to an increase in radiation- induced testicular damage.

Bench to Bedside: Animal Models of Radiation Induced Musculoskeletal Toxicity

Ionizing radiation is a critical aspect of current cancer therapy. While classically mature bone was thought to be relatively radio-resistant, more recent data have shown this to not be the case. Radiation therapy (RT)-induced bone loss leading to fracture is a source of substantial morbidity. The mechanisms of RT likely involve multiple pathways, including changes in angiogenesis and bone vasculature, osteoblast damage/suppression, and increased osteoclast activity. The majority of bone loss appears to occur rapidly after exposure to ionizing RT, with significant changes in cortical thickness being detectable on computed tomography (CT) within three to four months. Additionally, there is a dose–response relationship. Cortical thinning is especially notable in areas of bone that receive >40 gray (Gy). Methods to mitigate toxicity due to RT-induced bone loss is an area of active investigation. There is an accruing clinical trial investigating the use of risderonate, a bisphosphonate, to prevent rib bone loss in patients undergoing lung stereotactic body radiation therapy (SBRT). Additionally, several other promising therapeutic/preventative approaches are being explored in preclinical studies, including parathyroid hormone (PTH), amifostine, and mechanical loading of irradiated bones.