2-Methoxyestradiol Inhibits Radiation-Induced Skin Injuries

Luteolin target HSPB1 regulates endothelial cell ferroptosis to protect against radiation vascular injury

Vascular endothelial damage due to ionizing radiation is the main pathological process of radiation injury and the main cause of damage to various organs in nuclear accidents. Ferroptosis plays an important role in ionizing radiation-induced cell death. We have previously reported that luteolin is highly resistant to ferroptosis. In the present study, body weight, microvessel count, H&E, and Masson staining results showed that luteolin rescued radial vascular injury in vivo. Cell Counting Kit 8 (CCK8), Giemsa staining clarified the anti-ferroptosis ability of luteolin with low toxicity. Malondialdehyde (MDA), superoxide dismutase (SOD), NADP+/NADPH, Fe2+ staining, dihydroethidium (DHE) and MitoTracker assays for ferroptosis-related metrics, we found that luteolin enhances human umbilical vein endothelial cells (HUVECs) antioxidant damage capacity. Drug affinity responsive target stability (DARTS), surface plasmon resonance (SPR), computer simulated docking and western blot showed that heat shock protein beta-1 (HSPB1) is one of the targets of luteolin action. Luteolin inhibits ferroptosis by promoting the protein expression of HSPB1/solute carrier family 7 member 11 (SLC7A11)/ glutathione peroxidase 4 (GPX4). In conclusion, we have preliminarily elucidated the antioxidant damage ferroptosis ability and the target of action of luteolin to provide a theoretical basis for the application of luteolin in radiation injury diseases.

Radiation-induced skin reactions: oxidative damage mechanism and antioxidant protection

According to official statistics, cancer remains the main reason of death and over 50% of patients with cancer receive radiotherapy. However, adverse consequences after radiation exposure like radiation-induced skin reactions (RISR) have negative or even fatal impact on patients' quality of life (QoL). In this review we summarize the mechanisms and managements of RISRs, a process that involve a variety of extracellular and intracellular signals, among which oxidative stress (OS) are now commonly believed to be the initial part of the occurrence of all types of RISRs. As for the management of RISRs, traditional treatments have been widely used but without satisfying outcomes while some promising therapeutic strategies related to OS still need further researches. In the context we discuss how OS leads to the happening of RISRs of different types, hoping it can shed some light on the exploration of new countermeasures.

Preparing the soil: Adjusting the metabolic health of patients with chronic wounds and musculoskeletal diseases

In recent years, systemic inflammation has emerged as a pivotal player in the development and progression of various degenerative diseases. This complex, chronic inflammatory state, often undetected, can have far-reaching consequences for the body's physiology. At the molecular level, markers such as C-reactive protein, cytokines and other inflammatory mediators serve as indicators of systemic inflammation and often act as predictors of numerous musculoskeletal diseases and even certain forms of cancer. The concept of 'meta-inflammation', specifically referring to metabolically triggered inflammation, allows healthcare professionals to understand inflammatory responses in patients with metabolic syndrome. Driven by nutrient excess and the expansion of adipose tissue, meta-inflammation is closely associated with insulin resistance, further propagating the metabolic dysfunction observed in many Western societies. Wound persistence, on the other hand, exacerbates the detrimental effects of prolonged inflammation at the local level. Acute inflammation is a beneficial and essential process for wound healing and infection control. However, when inflammation fails to resolve, it can impede the healing process, leading to chronic wounds, excessive scarring and even the activation of fibrotic pathways. This approach significantly reduces the efficacy of regenerative biological therapies. Our review focuses on the vital role of proteins, vitamins and minerals in collagen synthesis and cell proliferation for tissue healing. We also examine hormonal influences on regeneration, noting the negative effects of imbalances, and emphasize glucose regulation's importance in creating a stable environment for chronic wound healing.

Molecular biological mechanisms of radiotherapy-induced skin injury occurrence and treatment

Radiotherapy-Induced Skin Injury (RISI) is radiation damage to normal skin tissue that primarily occurs during tumor Radiotherapy and occupational exposure. The risk of RISI is high due to the fact that the skin is not only the first body organ that ionizing radiation comes into contact with, but it is also highly sensitive to it, especially the basal cell layer and capillaries. Typical clinical manifestations of RISI include erythema, dry desquamation, moist desquamation, and ulcers, which have been established to significantly impact patient care and cancer treatment. Notably, our current understanding of RISI's pathological mechanisms and signaling pathways is inadequate, and no standard treatments have been established. Radiation-induced oxidative stress, inflammatory responses, fibrosis, apoptosis, and cellular senescence are among the known mechanisms that interact and promote disease progression. Additionally, radiation can damage all cellular components and induce genetic and epigenetic changes, which play a crucial role in the occurrence and progression of skin injury. A deeper understanding of these mechanisms and pathways is crucial for exploring the potential therapeutic targets for RISI. Therefore, in this review, we summarize the key mechanisms and potential treatment methods for RISI, offering a reference for future research and development of treatment strategies.

Multifunctional Glycopeptide-Based Hydrogel via Dual-Modulation for the Prevention and Repair of Radiation-Induced Skin Injury

The radiation-induced skin injury (RISI) remains a great challenge for clinical wound management and care after radiotherapy, as patients will suffer from the acute radiation injury and long-term chronic inflammatory damage during the treatment. The excessive ROS in the early acute stage and prolonged inflammatory response in the late healing process always hinder therapeutic efficiency. Herein, we developed an extracellular matrix (ECM)-mimetic multifunctional glycopeptide hydrogel (oCP@As) to promote and accelerate RISI repair via a dual-modulation strategy in different healing stages. The oCP@As hydrogel not only can form an ECM-like nanofiber structure through the Schiff base reaction but also exhibits ROS scavenging and DNA double-strand break repair abilities, which can effectively reduce the acute radiation damage. Meanwhile, the introduction of oxidized chondroitin sulfate, which is the ECM polysaccharide-like component, enables regulation of the inflammatory response by adsorption of inflammatory factors, accelerating the repair of chronic inflammatory injury. The animal experiments demonstrated that oCP@As can significantly weaken RISI symptoms, promote epidermal tissue regeneration and angiogenesis, and reduce pro-inflammatory cytokine expression. Therefore, this multifunctional glycopeptide hydrogel dressing can effectively attenuate RISI symptoms and promote RISI healing, showing great potential for clinical applications in radiotherapy protection and repair.

2-Methoxyestradiol inhibits the proliferation level in keloid fibroblasts through p38 in the MAPK/Erk signaling pathway

BACKGROUND

The MAPK/Erk signaling pathway is a classic pathway in cell proliferation. Our former study showed that keloid tissue revealed a higher proliferation level than physiological scars and normal skin. As a natural metabolite of estradiol, 2-methoxyestradiol (2ME2) showed an inhibition proliferation effect on tumor cells.

AIM

In this study, the treatment effect of 2ME2 and its potential mechanisms are explored.

METHODS

Six keloid patients and six non-keloid patients were randomly selected from the Department of Plastic Surgery at our hospital during June 2021 to December 2021. Six groups were established: normal skin fibroblasts (N); keloid fibroblasts (K); keloid fibroblasts treated with 2ME2 (K + 2ME2); keloid fibroblasts treated with dimethyl sulfoxide (DMSO) (K + DMSO); keloid fibroblasts treated with doramapimod (K + IN); keloid fibroblasts treated with doramapimod (p38 inhibitor) and 2ME2 (K + IN+2ME2). The fibroblast activity and key factor expression of the MAPK/Erk signaling pathway were measured.

RESULTS

In the results, 2ME2 significantly inhibited keloid fibroblast activity and key factor expression (except STAT1).

CONCLUSION

The proliferation levels were reduced by both the p38 inhibitor and 2ME2, indicating 2ME2 may achieve an antiproliferation effect by targeting p38 in keloid fibroblasts.

Tissue fibrosis induced by radiotherapy: current understanding of the molecular mechanisms, diagnosis and therapeutic advances

Cancer remains the leading cause of death around the world. In cancer treatment, over 50% of cancer patients receive radiotherapy alone or in multimodal combinations with other therapies. One of the adverse consequences after radiation exposure is the occurrence of radiation-induced tissue fibrosis (RIF), which is characterized by the abnormal activation of myofibroblasts and the excessive accumulation of extracellular matrix. This phenotype can manifest in multiple organs, such as lung, skin, liver and kidney. In-depth studies on the mechanisms of radiation-induced fibrosis have shown that a variety of extracellular signals such as immune cells and abnormal release of cytokines, and intracellular signals such as cGAS/STING, oxidative stress response, metabolic reprogramming and proteasome pathway activation are involved in the activation of myofibroblasts. Tissue fibrosis is extremely harmful to patients' health and requires early diagnosis. In addition to traditional serum markers, histologic and imaging tests, the diagnostic potential of nuclear medicine techniques is emerging. Anti-inflammatory and antioxidant therapies are the traditional treatments for radiation-induced fibrosis. Recently, some promising therapeutic strategies have emerged, such as stem cell therapy and targeted therapies. However, incomplete knowledge of the mechanisms hinders the treatment of this disease. Here, we also highlight the potential mechanistic, diagnostic and therapeutic directions of radiation-induced fibrosis.

2-Methoxyestradiol-3,17-O,O-bis-sulfamate (STX140) Inhibits Proliferation and Invasion via Senescence Pathway Induction in Human BRAFi-Resistant Melanoma Cells

The endogenous estradiol derivative 2-Methoxyestradiol (2-ME) has shown good and wide anticancer activity but suffers from poor oral bioavailability and extensive metabolic conjugation. However, its sulfamoylated derivative, 2-methoxyestradiol-3,17-O,O-bis-sulfamate (STX140), has superior potential as a therapeutic agent, acts by disrupting microtubule polymerization, leading to cell cycle arrest and apoptosis in cancer cells and possesses much better pharmaceutical properties. This study investigated the antiproliferative and anti-invasive activities of STX140 in both SKMEL-28 naïve melanoma (SKMEL28-P) cells and resistant melanoma cells (SKMEL-28R). STX140 inhibited cell proliferation in the nanomolar range while having a less pronounced effect on human melanocytes. Additionally, STX140 induced cell cycle arrest in the G2/M phase and sub-G1, reduced migration, and clonogenic potential in monolayer models, and inhibited invasion in a 3D human skin model with melanoma cells. Furthermore, STX140 induced senescence features in melanoma and activated the senescence machinery by upregulating the expression of senescence genes and proteins related to senescence signaling. These findings suggest that STX140 may hold potential as a therapeutic agent for melanoma treatment.

Multifunctional mesoporous silica-cerium oxide nanozymes facilitate miR129 delivery for high-quality healing of radiation-induced skin injury

Radiation-induced skin injury (RISI) is an important challenge for clinical treatments. The main causes of RISI include hypoxia in the wound microenvironment, reactive oxygen species (ROS) activation, and downregulation of DNA repair proteins. Here, a multiple radioresistance strategy was designed for microRNA therapy and attenuating hypoxia. A novel mesoporous silica (MS) firmly anchored and dispersed cerium (IV) oxide (CeO₂) nanoparticles to form MS-CeO₂ nanocomposites, which exhibit superior activity in inhibiting radiation-induced ROS and HIF-1α activation and ultimately promote RISI wound healing. The miR129 serum concentrations in patients can promote radioresistance by directly targeting RAD17 and regulating the Chk2 pathway. Subsequently, MS-CeO₂ nanocomposites with miR129 were conjugated with iRGD-grafted polyoxyethylene glycol (short for nano-miR129), which increased the stability and antibacterial character, efficiently delivered miR129 to wound blood capillaries, and exhibited low toxicity. Notably, nano-miR129 promoted radioresistance and enhanced anti-ROS therapeutic efficacy in a subcutaneous RISI mouse model. Overall, this MS-CeO₂ nanozyme and miR129-based multiresistance radiotherapy protection strategy provided a promising therapeutic approach for RISI.