Multifunctional carbomer based ferulic acid hydrogel promotes wound healing in radiation-induced skin injury by inactivating NLRP3 inflammasome

BACKGROUND

Radiation-induced skin injury is a significant adverse reaction to radiotherapy. However, there is a lack of effective prevention and treatment methods for this complication. Ferulic acid (FA) has been identified as an effective anti-radiation agent. Conventional administrations of FA limit the reaching of it on skin. We aimed to develop a novel FA hydrogel to facilitate the use of FA in radiation-induced skin injury.

METHODS

We cross-linked carbomer 940, a commonly used adjuvant, with FA at concentrations of 5%, 10%, and 15%. Sweep source optical coherence tomography system, a novel skin structure evaluation method, was applied to investigate the influence of FA on radiation-induced skin injury. Calcein-AM/PI staining, CCK8 assay, hemolysis test and scratch test were performed to investigate the biocompatibility of FA hydrogel. The reducibility of DPPH and ABTS radicals by FA hydrogel was also performed. HE staining, Masson staining, laser Doppler blood flow monitor, and OCT imaging system are used to evaluate the degree of skin tissue damage. Potential differentially expressed genes were screened via transcriptome analysis.

RESULTS

Good biocompatibility and in vitro antioxidant ability of the FA hydrogels were observed. 10% FA hydrogel presented a better mechanical stability than 5% and 15% FA hydrogel. All three concentrations of FA remarkably promoted the recovery of radiation-induced skin injury by reducing inflammation, oxidative conidiation, skin blood flow, and accelerating skin tissue reconstruction, collagen deposition. FA hydrogel greatly inhibiting the levels of NLRP3, caspase-1, IL-18, pro-IL-1β and IL-1β in vivo and vitro levels through restraining the activation of NLRP3 inflammasome. Transcriptome analysis indicated that FA might regulate wound healing via targeting immune response, inflammatory response, cell migration, angiogenesis, hypoxia response, and cell matrix adhesion.

CONCLUSIONS

These findings suggest that the novel FA hydrogel is a promising therapeutic method for the prevention and treatment of radiation-induced skin injury patients.

Fruits and their phytochemicals in mitigating the ill effects of ionizing radiation: review on the existing scientific evidence and way forward

Although helpful in treating cancer, exposure to ionizing radiation can sometimes cause severe side effects, negating its benefit. In addition to its use in clinics, a nontoxic radioprotective agent can also be beneficial in occupational settings where humans are occupationally exposed for prolonged periods to low doses of radiation. Scientific studies using laboratory animals have shown that the fruits Aegle marmelos, Capsicum annuum, Citrus aurantium, Citrullus lanatus, Crataegus microphylla, Eugenia jambolana, Emblica officinalis, Garcinia kola, Grewia asiatica, Hippophae rhamnoides, Malus baccata, Malpighia glabra or Malpighia emarginata, Mangifera indica, Prunus domestica, Prunus avium, Prunus armeniaca, Psoralea corylifolia, Punica granatum, Solanum lycopersicum, Terminalia chebula, Vaccinium macrocarpon, Vitis vinifera and Xylopia aethiopica, and the phytochemicals gallic acid, ellagic acid, quercetin, geraniin, corilagin, ascorbic acid, hesperetin, ursolic acid, lycopene, naringin, hesperidin, rutin, resveratrol, β-sitosterol, apigenin, luteolin, chlorogenic acid, caffeic acid, mangiferin, diosmin, ferulic acid, and kaempferol are effective in preventing radiation-induced ill effects. Clinical studies with Emblica officinalis and Punica granatum have also shown that fruits help mitigate radiation-induced mucositis, dermatitis, and cystitis. For the first time, the current review summarizes the beneficial effects of fruits and phytochemicals in mitigating radiation-induced damage, the underlying mechanisms and the existing lacunae for future studies to be undertaken for the benefit of humans and the nutraceutical and agri-based industries.

AP2a-Mediated Upregulation of miR-125a-5p Ameliorates Radiation-Induced Oxidative Stress Injury via BRD4/Nrf2/HO-1 Signaling

Radiation therapy is widely used to restrain tumor progression, but it is always accompanied by damage to healthy tissues. We aimed to probe the impact and mechanism of activator protein 2a (AP2a) and miR-125a-5p in radiation-induced oxidative stress injury. Human umbilical vein endothelial cells (HUVECs) were treated with X rays to induce radiation injury in vitro. Cell viability was measured using MTT assays. Flow cytometry assay was employed to detect the apoptosis rate. Oxidative stress markers were evaluated by detection kits. Gene or protein levels were determined by RT-qPCR or Western blotting. Validation of the interaction of miR-125a-5p with BRD4 and AP2a was conducted by dual luciferase assay or ChIP. MiR-125a-5p and AP2a were decreased in irradiated HUVECs, whereas BRD4 was increased. MiR-125a-5p overexpression or BRD4 silencing alleviated the cell viability decline, apoptosis, and oxidative stress injury caused by radiation treatment. MiR-125a-5p repressed the BRD4 level. The protective effects of miR-125a-5p overexpression in the radiation-induced oxidative injury were impeded by BRD4 overexpression. Moreover, AP2a bound to the promoter of miR-125a-5p. MiR-125a-5p inhibition reversed the effects of AP2a overexpression on radiational oxidative injury by modulating Nrf2/HO-1 signaling. AP2a transcriptionally activated miR-125a-5p ameliorated oxidative stress injury of HUVECs caused by radiation through Nrf2/HO-1 signaling.

Preclinical findings reveal the pharmacological targets of ferulic acid in the treatment of traumatic brain injury

Traumatic brain injury (TBI) is characterized by cellular damage and inflammation in lesioned brain tissue. Ferulic acid has been shown to have a melioration effect on neurological functions. However, the active pharmacological effects and the underlying mechanisms of ferulic acid against TBI remain unclear. On the basis of network pharmacology and molecular docking methodology, this study aimed to investigate the beneficial effects of ferulic acid in treating TBI, and characterized the detailed biotargets and mechanisms of these actions. The identified core targets were validated via in silico simulation. We identified 91 overlapping targets associated with ferulic acid and TBI. In-silico simulation analysis validated the putative core targets of tumor protein p53, mitogen-activated protein kinase (MAPK) 1, and estrogen receptor 1. The Gene Ontology-enriched annotations and findings were largely associated with cell proliferation, apoptosis, and inflammation in nerve cells. Additional Kyoto Encyclopedia of Genes and Genomes enrichment analysis unmasked the pharmacological pathways of ferulic acid in treating TBI, including the MAPK signaling pathway and hypoxia-inducible factor-1 signaling pathway. Bioinformatic analyses and findings provide a new preclinical strategy for revealing the core targets and network pathways of ferulic acid in treating TBI. Moreover, some bioinformatic findings were computationally validated in silico for exhibiting the neuroprotective action of ferulic acid against TBI.

Research progress on the mechanism of radiation enteritis

Radiation enteritis (Re) is one of the most common complications of radiation therapy for abdominal tumors. The efficacy of cancer treatment by radiation is often limited by the side effects of Re. Re can be acute or chronic. Treatment of acute Re is essentially symptomatic. However, chronic Re usually requires surgical procedures. The underlying mechanisms of Re are complex and have not yet been elucidated. The purpose of this review is to provide an overview of the pathogenesis of Re. We reviewed the role of intestinal epithelial cells, intestinal stem cells (ISCs), vascular endothelial cells (ECs), intestinal microflora, and other mediators of Re, noting that a better understanding of the pathogenesis of Re may lead to better treatment modalities.

Ferulic acid produces neuroprotection against radiation-induced neuroinflammation by affecting NLRP3 inflammasome activation

PURPOSE

After radiation therapy of brain tumors, radiation-induced cognitive impairment is a common and severe complication. Neuroinflammation mediated by microglia is a critical event that accelerates cognitive or functional decline. Ferulic acid (FA), a phenolic plant component, possesses multiple pharmacological effects, such as anti-inflammatory and anti-radiation. The current research attempts to ascertain the protection of FA on radiation-induced neuroinflammation and the mechanism of this effect.

MATERIALS AND METHODS

C57BL/6 mice were irradiated with ⁶⁰Co γ-ray to establish a brain injury model. The Morris water maze experiment was used to observe the effects of FA on the spatial learning and memory impairment of irradiated mice. The pathological changes of hippocampal tissue were observed by HE staining. Besides, microglia BV-2 cell lines were used to study the anti-neuroinflammatory impacts of FA on radiation-induced microglial activation and further elucidate the potential mechanisms influencing FA-mediated neuroprotective properties. The cell morphological changes were observed using an optical microscope. The cytotoxicity of FA and radiation to BV-2 cells was determined using the CCK-8 assay. Additionally, Western blot and quantitative real-time PCR detected the expression and transcription of NLRP3 inflammasome and pro-inflammatory cytokines in hippocampus and BV-2 cells.

RESULTS

FA could enhance learning and memory capacity and ameliorate pathological changes in the hippocampal tissues of irradiated mice. The cell radiation injury model was established by 8 Gy ⁶⁰Co γ-ray, and the concentration of subsequent administration was determined to be 2.5, 5, and 10 μmol/L. Furthermore, FA could suppress the transcription and expression of NLRP3 in hippocampal tissue and microglia, and also the increased secretion of pro-inflammatory factors.

CONCLUSION

This study established that FA targeting the NLRP3 inflammasome has a neuroprotective effect against radiation-induced nerve damage, implying that FA might have some potential in the treatment of radiation-induced cognitive impairment.

Ferulic acid and hormesis: Biomedical and environmental implications

The present paper provides the first systematic assessment of the capacity of ferulic acid to induce hormetic dose responses in biological systems. Ferulic acid induced hormetic effects in a broad range of animal models, affecting numerous biological endpoints, with particular focus on neuroprotective effects. Emerging evidence in multiple biomedical systems indicates that the hormetic effects of ferulic acid depend upon the activation of the transcription factor Nrf2. Ferulic acid was also shown to have an important role in ecological settings, being routinely released into the environment by numerous plant species, acting as an allelopathic agent affecting the growth of neighboring species via hormetic dose responses. These findings demonstrate the potential ecological and biomedical importance of ferulic acid effects and that these effects are commonly expressed via the hormetic dose response, suggesting complex multisystem evolutionary regulatory strategies.

Radiobiological Studies of Microvascular Damage through In Vitro Models: A Methodological Perspective

Ionizing radiation (IR) is used in radiotherapy as a treatment to destroy cancer. Such treatment also affects other tissues, resulting in the so-called normal tissue complications. Endothelial cells (ECs) composing the microvasculature have essential roles in the microenvironment's homeostasis (ME). Thus, detrimental effects induced by irradiation on ECs can influence both the tumor and healthy tissue. In-vitro models can be advantageous to study these phenomena. In this systematic review, we analyzed in-vitro models of ECs subjected to IR. We highlighted the critical issues involved in the production, irradiation, and analysis of such radiobiological in-vitro models to study microvascular endothelial cells damage. For each step, we analyzed common methodologies and critical points required to obtain a reliable model. We identified the generation of a 3D environment for model production and the inclusion of heterogeneous cell populations for a reliable ME recapitulation. Additionally, we highlighted how essential information on the irradiation scheme, crucial to correlate better observed in vitro effects to the clinical scenario, are often neglected in the analyzed studies, limiting the translation of achieved results.

Tritiated Water Induces Toxicity in Human Umbilical Vein Vascular Endothelial Cells via IL8

We aimed to determine the toxic effects of tritiated water (HTO) on 12 generations (T1-T12) of human umbilical vein vascular endothelial cells (HUVECs) and elucidate the underlying mechanisms. We evaluated cellular senescence, interleukin (IL) 8 concentrations, and angiogenesis using β-galactosidase staining, enzyme-linked immunosorbent assay, and in vitro assays, respectively. The adhesion properties of contaminated cells and differentially expressed genes were assessed using the xCELLigence RTCA SP system and gene chip analysis, respectively. We found that long-term exposure to low levels of HTO can reduce the adhesion of HUVECs to the cellular matrix as well as their angiogenic capacity, while increasing their permeability, senescence, and adhesion to monocytes. Interleukin 8 activated the p38 and Epidermal Growth Factor Receptor (EGFR) pathways in HTO-treated cells and hence was identified as a key candidate of biomarker. The present study clarified the toxicity of HTO in vascular endothelial cells and identified IL8 as a novel protective target with important theoretical and practical values.