Curcumin protects against radiation-induced acute and chronic cutaneous toxicity in mice and decreases mRNA expression of inflammatory and fibrogenic cytokines

Nrf-2 as a novel target in radiation induced lung injury

Radiation-induced lung injury (RILI) is a common and fatal complication of chest radiotherapy. The underlying mechanisms include radiation-induced oxidative stress caused by damage to the deoxyribonucleic acid (DNA) and production of reactive oxygen species (ROS), resulting in apoptosis of lung and endothelial cells and recruitment of inflammatory cells and myofibroblasts expressing NADPH oxidase to the site of injury, which in turn contribute to oxidative stress and cytokine production. Nuclear factor erythroid 2-related factor 2 (Nrf-2) is a vital transcription factor that regulates oxidative stress and inhibits inflammation. Studies have shown that Nrf-2 protects against radiation-induced lung inflammation and fibrosis. This review discusses the protective role of Nrf-2 in RILI and its possible mechanisms.

Deciphering the fibrotic process: mechanism of chronic radiation skin injury fibrosis

This review explores the mechanisms of chronic radiation-induced skin injury fibrosis, focusing on the transition from acute radiation damage to a chronic fibrotic state. It reviewed the cellular and molecular responses of the skin to radiation, highlighting the role of myofibroblasts and the significant impact of Transforming Growth Factor-beta (TGF-β) in promoting fibroblast-to-myofibroblast transformation. The review delves into the epigenetic regulation of fibrotic gene expression, the contribution of extracellular matrix proteins to the fibrotic microenvironment, and the regulation of the immune system in the context of fibrosis. Additionally, it discusses the potential of biomaterials and artificial intelligence in medical research to advance the understanding and treatment of radiation-induced skin fibrosis, suggesting future directions involving bioinformatics and personalized therapeutic strategies to enhance patient quality of life.

Evidence for the use of curcumin in radioprotection and radiosensitization

Curcumin has antineoplastic properties and is considered a chemotherapeutic and chemopreventive agent. Curcumin may be associated with radiation therapy (RT) as a radiosensitizer for cancer cells and a radioprotector for normal cells. In principle, it may result in a reduction of RT dosage for the same therapeutic effect on cancer cells, and further reduced damage to normal cells. Though the overall level of evidence is modest, limited to in vivo and in vitro experiences and practically no clinical trials, as the risks of adverse effects are extremely low, it is reasonable to promote the general supplementation with curcumin during RT targeting the reduction of side effects through anti-inflammatory mechanisms.

Combination of phytochemicals, including ginsenoside and curcumin, shows a synergistic effect on the recovery of radiation-induced toxicity

Radiotherapy is commonly used to treat solid cancers located in the pelvis. A considerable number of patients experience proctitis of varying severity, even for a considerable period after radiotherapy. These side effects are often long-lasting or progressively worsen despite multiple therapeutic efforts and are a primary cause of an unexpectedly low quality of life, even after successful cancer treatment. Therefore, this study evaluated the individual and combined efficacy of ginsenoside, curcumin, butyric acid, and sucralfate compounds in treating radiation-induced proctitis. While the candidate compounds did not affect the proliferation and migration of cancer cells, they promoted the recovery of cell activity, including motility. They exhibited anti-inflammatory effects on human dermal fibroblasts or human umbilical vein endothelial cells within in vitro disease models. When each compound was tested, curcumin and ginsenoside were the most effective in cell recovery and promoted the migration of human dermal fibroblasts and cell restoration of human umbilical vein endothelial cells. The combination of ginsenoside and curcumin resulted in cell migration recovery of approximately 54%. In addition, there was a significant improvement in the length of the endothelial tube, with an increase of approximately 25%, suggesting that the ginsenoside-curcumin-containing combination was the most effective against radiation-induced damage. Furthermore, studies evaluating the effects of combined treatments on activated macrophages indicated that the compounds effectively reduced the secretion of inflammatory cytokines, including chemokines, and alleviated radiation-induced inflammation. In conclusion, our study provides valuable insights into using curcumin and ginsenoside as potential compounds for the effective treatment of radiation-induced injuries and highlights the promising therapeutic benefits of combining these two compounds.

Connection between Radiation-Regulating Functions of Natural Products and miRNAs Targeting Radiomodulation and Exosome Biogenesis

Exosomes are cell-derived membranous structures primarily involved in the delivery of the payload to the recipient cells, and they play central roles in carcinogenesis and metastasis. Radiotherapy is a common cancer treatment that occasionally generates exosomal miRNA-associated modulation to regulate the therapeutic anticancer function and side effects. Combining radiotherapy and natural products may modulate the radioprotective and radiosensitizing responses of non-cancer and cancer cells, but there is a knowledge gap regarding the connection of this combined treatment with exosomal miRNAs and their downstream targets for radiation and exosome biogenesis. This review focuses on radioprotective natural products in terms of their impacts on exosomal miRNAs to target radiation-modulating and exosome biogenesis (secretion and assembly) genes. Several natural products have individually demonstrated radioprotective and miRNA-modulating effects. However, the impact of natural-product-modulated miRNAs on radiation response and exosome biogenesis remains unclear. In this review, by searching through PubMed/Google Scholar, available reports on potential functions that show radioprotection for non-cancer tissues and radiosensitization for cancer among these natural-product-modulated miRNAs were assessed. Next, by accessing the miRNA database (miRDB), the predicted targets of the radiation- and exosome biogenesis-modulating genes from the Gene Ontology database (MGI) were retrieved bioinformatically based on these miRNAs. Moreover, the target-centric analysis showed that several natural products share the same miRNAs and targets to regulate radiation response and exosome biogenesis. As a result, the miRNA-radiomodulation (radioprotection and radiosensitization)-exosome biogenesis axis in regard to natural-product-mediated radiotherapeutic effects is well organized. This review focuses on natural products and their regulating effects on miRNAs to assess the potential impacts of radiomodulation and exosome biogenesis for both the radiosensitization of cancer cells and the radioprotection of non-cancer cells.

Exploring Natural Products as Radioprotective Agents for Cancer Therapy: Mechanisms, Challenges, and Opportunities

Radiotherapy is an important cancer treatment. However, in addition to killing tumor cells, radiotherapy causes damage to the surrounding cells and is toxic to normal tissues. Therefore, an effective radioprotective agent that prevents the deleterious effects of ionizing radiation is required. Numerous synthetic substances have been shown to have clear radioprotective effects. However, most of these have not been translated for use in clinical applications due to their high toxicity and side effects. Many medicinal plants have been shown to exhibit various biological activities, including antioxidant, anti-inflammatory, and anticancer activities. In recent years, new agents obtained from natural products have been investigated by radioprotection researchers, due to their abundance of sources, high efficiency, and low toxicity. In this review, we summarize the mechanisms underlying the radioprotective effects of natural products, including ROS scavenging, promotion of DNA damage repair, anti-inflammatory effects, and the inhibition of cell death signaling pathways. In addition, we systematically review natural products with radioprotective properties, including polyphenols, polysaccharides, alkaloids, and saponins. Specifically, we discuss the polyphenols apigenin, genistein, epigallocatechin gallate, quercetin, resveratrol, and curcumin; the polysaccharides astragalus, schisandra, and Hohenbuehelia serotina; the saponins ginsenosides and acanthopanax senticosus; and the alkaloids matrine, ligustrazine, and β-carboline. However, further optimization through structural modification, improved extraction and purification methods, and clinical trials are needed before clinical translation. With a deeper understanding of the radioprotective mechanisms involved and the development of high-throughput screening methods, natural products could become promising novel radioprotective agents.

Polyphenols as Potential Protectors against Radiation-Induced Adverse Effects in Patients with Thoracic Cancer

Radiotherapy is one of the standard treatment approaches used against thoracic cancers, occasionally combined with chemotherapy, immunotherapy and molecular targeted therapy. However, these cancers are often not highly sensitive to standard of care treatments, making the use of high dose radiotherapy necessary, which is linked with high rates of radiation-induced adverse effects in healthy tissues of the thorax. These tissues remain therefore dose-limiting factors in radiation oncology despite recent technological advances in treatment planning and delivery of irradiation. Polyphenols are metabolites found in plants that have been suggested to improve the therapeutic window by sensitizing the tumor to radiotherapy, while simultaneously protecting normal cells from therapy-induced damage by preventing DNA damage, as well as having anti-oxidant, anti-inflammatory or immunomodulatory properties. This review focuses on the radioprotective effect of polyphenols and the molecular mechanisms underlying these effects in the normal tissue, especially in the lung, heart and esophagus.

Efficacy of curcumin for amelioration of radiotherapy-induced oral mucositis: a preliminary randomized controlled clinical trial

BACKGROUND

Oral mucositis (OM) is one of the main problems in almost all patients undergoing head and neck radiotherapy (RT). Owning to the antioxidant and anti-inflammatory properties of curcumin, the effect of both oral and topical formulations of curcumin was assessed on radiation-induced OM (ROM) in this study.

METHODS

The safety and efficacy of curcumin mouthwash 0.1% (w/v) and curcumin-nanocapsule were evaluated in ameliorating severity and pain/burning associated with OM during RT. The current randomized, placebo-controlled trial was conducted on 37 patients with head and neck cancers. Patients with grades 1 to 3 of ROM were randomized to receive one of the three interventions: curcumin mouthwash (0.1% w/v); Sinacurcumin soft gel containing 40 mg curcuminoids as nano-micelles (SinaCurcumin®40); or placebo mouthwash with a similar transparent appearance to curcumin mouthwash for 1 min three times daily during RT. Study evaluations were conducted at baseline and weekly thereafter for up to 3 weeks using the Numeric rating scale (NRS) and world health organization (WHO) scale.

RESULTS

Among the 45 patients randomized, 37 (mean (SD) age of 53.36 (15.99) years; 14 [37.8%] women) completed the treatment according to the protocol. Patients treated with either oral or topical curcumin showed a significantly reduced severity and burning related to OM during the first 3 weeks after administration (P-Value < 0.001) as compared with the placebo. At study termination, more than 33% of subjects utilizing curcumin mouthwash and 15% of patients utilizing curcumin-nanocapsule remained ulcer free while all of the placebo-receiving subjects had OM. The reduction of NRS and WHO scale between curcumin groups was comparable without significant differences.

CONCLUSION

Both curcumin mouthwash and nanocapsule were effective, safe, and well-tolerated in the treatment of radiation-induced OM. Higher doses of curcumin and larger sample sizes can be used for further investigation in future studies.

TRIAL REGISTRATION

https://irct.ir/ IRCT20190810044500N17 (13/08/2021).

Effects of oral supplementation to manage radiation dermatitis in cancer patients: a systematic review

PURPOSE

To evaluate the effectiveness and safety of oral supplementation as a radioprotective intervention in the management of radiation dermatitis (RD).

METHODS

Systematic review and meta-analysis. Six databases and the gray literature were searched for randomized controlled clinical trials (RCTs). Meta-analysis was performed only with studies that evaluated the same intervention. Methodology of included studies was evaluated by the Cochrane risk-of-bias tool for randomized trials (RoB 2.0), and the certainty of evidence was assessed by the GRADE instrument.

RESULTS

Seventeen RCTs were included in this review. These evaluated different types of oral supplementations. Findings from three meta-analyses demonstrated no significant benefits to the more severe grades of RD, as oral curcuminoids (RR, 0.59; 95% CI, 0.27 to 1.29; P = 0.19; I² = 88%), glutamine (RR, 0.40; 95% CI, 0.15 to 1.03; P = 0.06; I² = 78%) or Wobe-Mugos (RR, 0.57; 95% CI, 0.29 to 1.14; P = 0.11; I² = 72%). Also, the certainty of the evidence of outcomes evaluated was moderate or low. Except for a few gastrointestinal adverse events, oral supplementation was well tolerated.

CONCLUSION

Most oral supplements cannot yet be recommended to manage RD due to insufficient or conflicting evidence. However, despite no significant results, glutamine was shown to be a promising substance in terms of the potential radioprotective effect and may be well tolerated. These results suggest that more RCTs with larger samples are needed to evaluate the efficacy, safety, and tolerance of glutamine in the management of RD.

Therapeutic effect of turmeric on radiodermatitis: A systematic review

Radiodermatitis (RD) occurs in 95% of cancer patients undergoing radiation therapy. At present, there is no effective treatment for the management of this complication of radiotherapy. Turmeric (Curcuma longa) is a polyphenolic and biologically active natural compound with various pharmacological functions. The aim of this systematic review was to determine the efficacy of curcumin supplementation for reducing RD severity. This review complied with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. A comprehensive literature search was conducted in Cochrane library, PubMed, Scopus, Web of Science, and MEDLINE databases. A total of seven studies comprising 473 cases and 552 controls were included in this review. Four studies demonstrated that curcumin supplementation had a beneficial effect on RD intensity. These data provide evidence for the potential clinical use of curcumin in supportive cancer care. Further large prospective and well-designed trials are warranted to exactly determine the "real effective extract, supplemental form and dose of curcumin" for RD prevention and treatment of patients receiving radiotherapy.

High-throughput screening strategies for space-based radiation countermeasure discovery

As humanity begins to venture further into space, approaches to better protect astronauts from the hazards found in space need to be developed. One particular hazard of concern is the complex radiation that is ever present in deep space. Currently, it is unlikely enough spacecraft shielding could be launched that would provide adequate protection to astronauts during long-duration missions such as a journey to Mars and back. In an effort to identify other means of protection, prophylactic radioprotective drugs have been proposed as a potential means to reduce the biological damage caused by this radiation. Unfortunately, few radioprotectors have been approved by the FDA for usage and for those that have been developed, they protect normal cells/tissues from acute, high levels of radiation exposure such as that from oncology radiation treatments. To date, essentially no radioprotectors have been developed that specifically counteract the effects of chronic low-dose rate space radiation. This review highlights how high-throughput screening (HTS) methodologies could be implemented to identify such a radioprotective agent. Several potential target, pathway, and phenotypic assays are discussed along with potential challenges towards screening for radioprotectors. Utilizing HTS strategies such as the ones proposed here have the potential to identify new chemical scaffolds that can be developed into efficacious radioprotectors that are specifically designed to protect astronauts during deep space journeys. The overarching goal of this review is to elicit broader interest in applying drug discovery techniques, specifically HTS towards the identification of radiation countermeasures designed to be efficacious towards the biological insults likely to be encountered by astronauts on long duration voyages.

Curcumin Nanodiscs Improve Solubility and Serve as Radiological Protectants against Ionizing Radiation Exposures in a Cell-Cycle Dependent Manner

Curcumin, a natural polyphenol derived from the spice turmeric (Curcuma longa), contains antioxidant, anti-inflammatory, and anti-cancer properties. However, curcumin bioavailability is inherently low due to poor water solubility and rapid metabolism. Here, we further refined for use curcumin incorporated into "biomimetic" nanolipoprotein particles (cNLPs) consisting of a phospholipid bilayer surrounded by apolipoprotein A1 and amphipathic polymer scaffolding moieties. Our cNLP formulation improves the water solubility of curcumin over 30-fold and produces nanoparticles with ~350 µg/mL total loading capacity for downstream in vitro and in vivo applications. We found that cNLPs were well tolerated in AG05965/MRC-5 human primary lung fibroblasts compared to cultures treated with curcumin solubilized in DMSO (curDMSO). Pre-treatment with cNLPs of quiescent G0/G1-phase MRC-5 cultures improved cell survival following ¹³⁷Cs gamma ray irradiations, although this finding was reversed in asynchronously cycling log-phase cell cultures. These findings may be useful for establishing cNLPs as a method to improve curcumin bioavailability for administration as a radioprotective and/or radiomitigative agent against ionizing radiation (IR) exposures in non-cycling cells or as a radiosensitizing agent for actively dividing cell populations, such as tumors.

Phytochemicals Targeting Oxidative Stress, Interconnected Neuroinflammatory, and Neuroapoptotic Pathways Following Radiation

The radiation for therapeutic purposes has shown positive effects in different contexts; however, it can increase the risk of many age-related and neurodegenerative diseases such as Alzheimer's disease (AD), amyotrophic lateral sclerosis (ALS), Huntington's disease (HD), and Parkinson's disease (PD). These different outcomes highlight a dose-response phenomenon called hormesis. Prevailing studies indicate that high doses of radiation could play several destructive roles in triggering oxidative stress, neuroapoptosis, and neuroinflammation in neurodegeneration. However, there is a lack of effective treatments in combating radiation-induced neurodegeneration, and the present drugs suffer from some drawbacks, including side effects and drug resistance. Among natural entities, polyphenols are suggested as multi-target agents affecting the dysregulated pathogenic mechanisms in neurodegenerative disease. This review discusses the destructive effects of radiation on the induction of neurodegenerative diseases by dysregulating oxidative stress, apoptosis, and inflammation. We also describe the promising effects of polyphenols and other candidate phytochemicals in preventing and treating radiation-induced neurodegenerative disorders, aiming to find novel/potential therapeutic compounds against such disorders.

Cutaneous and local radiation injuries

The threat of a large-scale radiological or nuclear (R/N) incident looms in the present-day climate, as noted most recently in an editorial in Scientific American (March 2021). These large-scale incidents are infrequent but affect large numbers of people. Smaller-scale R/N incidents occur more often, affecting smaller numbers of people. There is more awareness of acute radiation syndrome (ARS) in the medical community; however, ionising radiation-induced injuries to the skin are much less understood. This article will provide an overview of radiation-induced injuries to the skin, deeper tissues, and organs. The history and nomenclature; types and causes of injuries; pathophysiology; evaluation and diagnosis; current medical management; and current research of the evaluation and management are presented. Cutaneous radiation injuries (CRI) or local radiation injuries (LRI) may lead to cutaneous radiation syndrome, a sub-syndrome of ARS. These injuries may occur from exposure to radioactive particles suspended in the environment (air, soil, water) after a nuclear detonation or an improvised nuclear detonation (IND), a nuclear power plant incident, or an encounter with a radioactive dispersal or exposure device. These incidents may also result in a radiation-combined injury; a chemical, thermal, or traumatic injury, with radiation exposure. Skin injuries from medical diagnostic and therapeutic imaging, medical misadministration of nuclear medicine or radiotherapy, occupational exposures (including research) to radioactive sources are more common but are not the focus of this manuscript. Diagnosis and evaluation of injuries are based on the scenario, clinical picture, and dosimetry, and may be assisted through advanced imaging techniques. Research-based multidisciplinary therapies, both in the laboratory and clinical trial environments, hold promise for future medical management. Great progress is being made in recognising the extent of injuries, understanding their pathophysiology, as well as diagnosis and management; however, research gaps still exist.

Curcumin supplementation in pediatric patients: A systematic review of current clinical evidence

This systematic review was designed to determine the clinical efficacy and safety of curcumin supplementation for pediatric patients based on clinical trials in children. We systematically searched electronic databases including PubMed, EMBASE, Web of Science, and Scopus for all studies that investigated curcumin administration in the pediatric population without any time frame limitation. Finally, we identified 16 studies for this review. Clinical efficacy and safety of curcumin were assessed in children with inflammatory and immune disorders (including asthma, inflammatory bowel disease (IBD), and juvenile idiopathic arthritis (JIA)), metabolic disorders, autosomal dominant polycystic kidney disease (ADPKD), cystic fibrosis (CF), tetralogy of Fallot (TOF), and infectious diseases. Curcumin was administered in a wide range of doses (45 mg-4,000 mg daily) and durations (2-48 weeks). Overall, curcumin was well tolerated in all studies and improved the severity of inflammatory and immune disorders and metabolic diseases. However, more studies are needed to clarify the role of curcumin supplementation among children with ADPKD, CF, TOF, and infectious diseases. Because of substantial heterogeneity in methodological quality, design, outcomes, dose, duration of intake, formulations, and study populations across studies, no quantitative analysis was performed. Additional large-scale, randomized, placebo-controlled clinical trials are needed to confirm the results of the conducted studies.

Targeting of the tumor microenvironment by curcumin

The tumor microenvironment (TME) is made up of several cells and molecules that affect the survival of cancer cells. Indeed, certain (immunosuppressive) cells which promote tumors can promote the growth of tumors by stimulating the proliferation of cancer cells and promoting angiogenesis. During tumor growth, antitumoral immunity includes natural killer cells and CD8+ T cells cannot overcome immunosuppressive responses and cancer cell proliferation. In order to achieve the appropriate therapeutic response, we must kill cancer cells and suppress the release of immunosuppressive molecules. The balance between anti-tumor immunity and immunosuppressive cells, such as regulatory T cells (Tregs), cancer-associated fibroblasts, tumor-associated macrophages, and myeloid-derived suppressor cells plays a key role in the suppression or promotion of cancer cells. Curcumin is a plant-derived agent that has shown interesting properties for cancer therapy. It has shown that not only directly inhibit the growth of cancer cells, but can also modulate the growth and activity of immunosuppressant and tumor-promoting cells. In this review, we explain how curcumin modulates interactions within TME in favor of tumor treatment. The potential modulating effects of curcumin on the responses of cancer cells to treatment modalities such as immunotherapy will also be discussed.

Radioprotective Role of Natural Polyphenols: From Sources to Mechanisms

The identification and development of radioprotective agents has emerged as a subject matter of research during recent years due to the growing usage of ionizing radiation in different areas of human life. Previous work on synthetic radioprotectors has achieved limited progress because of the numerous issues associated with toxicity. Compounds extracted from plants have potential to serve as lead candidates for developing ideal radioprotectors due to their low cost, safety and selectivity. Polyphenols are the most abundant and commonly dispersed group of biologically active molecules possessing broad range of pharmacological activities. Polyphenols have displayed efficacy for radioprotection during various investigations and can be administered at high doses with lesser toxicity. Detoxification of free radicals, modulating inflammatory responses, DNA repair, stimulation of hematopoietic recovery, and immune functions are the main mechanisms for radiation protection with polyphenols. Epicatechin, epigallocatechin-3-gallate, apigenin, caffeic acid phenylethylester, and silibinin provide cytoprotection together with the suppression of many pro-inflammatory cytokines owing to their free radical scavenging, anti-oxidant, and anti-inflammatory properties. Curcumin, resveratrol, quercetin, gallic acid, and rutin's radioprotective properties are regulated primarily by direct or indirect decline in cellular stress. Thus, polyphenols may serve as potential candidates for radioprotection in the near future, however, extensive investigations are still required to better understand their protection mechanisms.

Radioprotective Potential of Nutraceuticals and their Underlying Mechanism of Action

Radiations are an efficient treatment modality in cancer therapy. Besides the treatment effects of radiations, the ionizing radiations interact with biological systems and generate reactive oxygen species that interfere with the normal cellular process. Previous investigations of synthetic radioprotectors have shown less effectiveness, mainly owing to some limiting effects. The nutraceuticals act as efficient radioprotectors to protect the tissues from the deleterious effects of radiation. The main radioprotection mechanism of nutraceuticals is the scavenging of free radicals while other strategies are involved modulation of signaling transduction of pathways like MAPK (JNK, ERK1/2, ERK5, and P38), NF-kB, cytokines, and their protein regulatory genes expression. The current review is focused on the radioprotective effects of nutraceuticals including vitamin E, -C, organosulphur compounds, phenylpropanoids, and polysaccharides. These natural entities protect against radiation-induced DNA damage. The review mainly entails the antioxidant perspective and mechanism of action of their radioprotective activities on a molecular level, DNA repair pathway, anti-inflammation, immunomodulatory effects, the effect on cellular signaling pathways, and regeneration of hematopoietic cells.

Influence of common dietary supplements (curcumin, andrographolide, and d-limonene) on the radiobiological responses of p53-competent colonic cancer epithelial cells

PURPOSE

The main goal of the research was to determine whether commercially available common dietary phytochemical supplements (curcumin, andrographolide, and d-limonene) have radiomodulatory effects on p53-competent human colonic epithelial cells.

METHODS

Clonogenic survival assays were used to characterize effects of the phytochemicals on cultured colonic epithelial cells (HCT116 p53^+/+) in direct irradiation or upon receipt of irradiated-cell conditioned media (for bystander effects). In direct irradiation, feeding regimen experiments included compound administration pre- and post-irradiation, which was used as a basis to define effects as radioprotective and radiomitigative, respectively. In the bystander effect experiments, either donor or recipient cell cultures were fed with the phytochemicals and bystander-induced clonogenic cell death was quantitatively evaluated. Dose challenge was in the range of 0.5 - 5 Gy using the gamma source (Cs-137).

RESULTS

Curcumin, andrographolide, and d-limonene appeared to not exhibit radioprotective and radiomitigative properties in HCT116 p53^+/+ cells. D-limonene was found to induce radiosensitization in post-irradiation administration. All three compounds appeared not to modulate the radiation-induced bystander signal production and response in HCT116 p53^+/+ cells.

CONCLUSIONS

Curcumin, andrographolide, and d-limonene are known to have many chemoprotective benefits. This work shows that they, however, did not protect colonic epithelial HCT116 p53^+/+ cells from radiation killing. As HCT116 p53^+/+ cells are tumourigenic in nature, this finding implies that these three dietary compounds would not reduce the killing efficacy of radiation in gastrointestinal tumorigenesis. The post-irradiation radiosensitizing effect of d-limonene was an intriguing observation worth further investigation.

The effect of oral curcumin supplementation on health-related quality of life: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND AND AIMS

With an aging society, a multitude of physical, mental, and emotional challenges are being faced both in the general population and by those with chronic disorders. An enhanced understanding of 'quality of life' could be considered a major criterion for improved clinical care. We performed a meta-analysis to examine the effect of oral curcumin on improving the health-related quality of life (HRQOL).

METHODS

A systematic search was performed through PubMed, Clarivate Web of Science, Scopus, and Embase up to February 2020 using relevant keywords. Trials that met the inclusion criteria were included in this study. We applied the standardized mean difference (SMD) in a random-effects model to analyze the impact of combined trials. Additionally, we used the Cochrane Risk Bias Tool to evaluate any potential risks of bias.

RESULTS

A total of 10 studies were considered eligible and included in the meta-analysis. We found an overall significant effect of oral curcumin supplementation on improved HRQOL (SMD: 2.46, 95% CI: 1.30, 3.63; I2=97.4). In the subgroup analysis, curcumin showed significantly favorable effects on HRQOL in trials with a short duration of curcumin intervention (<5 months) and those that used curcumin formulations with high bioavailability.

CONCLUSION

Oral curcumin has a strong positive impact on HRQOL. Our analysis supports the use of an improved-bioavailability formulation of curcumin to improve HRQOL. However, given the heterogeneity among the studies included in this review, additional evidence from well-designed, large, and long-term trials is still required.

Biological Effects of Scattered Versus Scanned Proton Beams on Normal Tissues in Total Body Irradiated Mice: Survival, Genotoxicity, Oxidative Stress and Inflammation

Side effects of proton therapy are poorly studied. Moreover, the differences in the method of dose delivery on normal tissues are not taken into account when proton beams are scanned instead of being scattered. We proposed here to study the effects of both modalities of proton beam delivery on blood; skin; lung and heart in a murine model. In that purpose; C57BL/6 mice were total body irradiated by 190.6 MeV proton beams either by Double Scattering (DS) or by Pencil Beam Scanning (PBS) in the plateau phase before the Bragg Peak. Mouse survival was evaluated. Blood and organs were removed three months after irradiation. Biomarkers of genotoxicity; oxidative stress and inflammation were measured. Proton irradiation was shown to increase lymphocyte micronucleus frequency; lung superoxide dismutase activity; erythrocyte and skin glutathione peroxidase activity; erythrocyte catalase activity; lung; heart and skin oxidized glutathione level; erythrocyte and lung lipid peroxidation and erythrocyte protein carbonylation even 3 months post-irradiation. When comparing both methods of proton beam delivery; mouse survival was not different. However, PBS significantly increased lymphocyte micronucleus frequency; erythrocyte glutathione peroxidase activity and heart oxidized glutathione level compared to DS. These results point out the necessity to take into account the way of delivering dose in PT as it could influence late side effects.

Curcumin as a preventive or therapeutic measure for chemotherapy and radiotherapy induced adverse reaction: A comprehensive review

Curcumin has attracted much attention for medicinal purposes in wide range of illnesses including cancer. In some studies, its efficacy is evaluated against chemotherapy and radiotherapy induced adverse reaction and also as adjuvant to cancer treatment. Here we have tried to present a comprehensive review on protective and therapeutic effect of curcumin against these side effects. METHOD: The data were collected by searching Scopus, PubMed, Medline, and Cochrane database systematic reviews, using key words "nephrotoxicity", "cardiotoxicity", "genotoxicity", "ototoxicity", "hepatotoxicity", "reproductive toxicity", "myelosuppression", "pulmonary toxicity", "radiotherapy induced side effect" with "turmeric" and "curcumin". Although curcumin has low bioavailability, it has shown brilliant profile on prevention and management of chemotherapy and radiotherapy induced adverse reactions, particularly based on in vitro and in vivo studies and limited number of human studies on radiotherapy adverse reactions. Antioxidant and anti-inflammatory properties of the curcumin are the main proposed mechanism of action for management and prevention of adverse reactions. One of the major points regarding the protective effect of curcumin is its wide tolerable therapeutic range of dose with minimal side effects. Furthermore, new nano-formulations help to improve the bioavailability, increase in efficacy and lower the adverse effects. In conclusion, based on the present knowledge, curcumin has significant supportive potential in patients receiving chemotherapy or radiotherapy and may be suggested as adjutant with cancer treatments. Further well-designed human studies are recommended.

The Influence of Piperine on the Radioprotective Effect of Curcumin in Irradiated Human Lymphocytes

Objectives

Ionizing radiation (IR) induces DNA damage in normal cells, leading to genotoxicity. The radioprotective effects of co-treatment with curcumin and piperine were investigated against genotoxicity induced by IR in human normal lymphocytes.

Materials and Methods

Human blood samples were pretreated with curcumin at different concentrations (5, 10, and 25 μg/mL) and/or piperine (2.5 μg/mL) and then were exposed to IR at a dose 1.5 Gy. The radioprotective effects of curcumin and piperine were assessed by micronucleus (MN) assay.

Results

Curcumin and piperine reduced the percentage of MN induced by IR in lymphocytes. Piperine alone significantly reduced genotoxicity induced by IR as compared to curcumin alone at all concentrations. An additive radioprotective effect was observed with combination of piperine and curcumin at the low concentration of 5 μg/mL, while this synergistic effect was not observed with curcumin at the higher concentrations of 10 and 25 μg/mL.

Conclusion

Piperine has a potent radioprotective effect at low concentration as compare to curcumin. However, an additive radioprotective effect was observed with co-treatment with piperine and curcumin at low concentration, while piperine increased the percentage of MN in normal lymphocytes when co-treated with curcumin at higher concentration.

Pharmacological management of ionizing radiation injuries: current and prospective agents and targeted organ systems

Introduction: There is a limited array of currently available medicinals that are useful for either the prevention, mitigation or treatment of bodily injuries arising from ionizing radiation exposure.Area covered: In this brief article, the authors review those pharmacologic agents that either are currently being used to counter the injurious effects of radiation exposure, or those that show promise and are currently under development.Expert opinion: Although significant, but limited progress has been made in the development and fielding of safe and effective pharmacotherapeutics for select types of acute radiation-associated injuries, additional effort is needed to broaden the scope of drug development so that overall health risks associated with both short- and long-term injuries in various organ systems can be reduced and effectively managed. There are several promising radiation countermeasures that may gain regulatory approval from the government in the near future for use in clinical settings and in the aftermath of nuclear/radiological exposure contingencies.

Possible curative role of curcumin and silymarin against nephrotoxicity induced by gamma-rays in rats

Curcumin (CUR) and silymarin (SLM) are powerful antioxidant and anti-inflammatory compounds with beneficial protective effects against renal diseases. The purpose of this study was to evaluate the efficacy of CUR and SLM alone or in combination on radiation (IR) induced kidney injury. The results showed that CUR and SLM alone or in combination attenuated the oxidative stress denoted by a reduction in the level of malondialdehyde (MDA), hydrogen peroxide (H₂O₂) and advanced oxidation protein products (AOPP) along with a marked increase of glutathione GSH content and total antioxidant capacity (TAC). Additionally, a significant decrease in the level of blood urea nitrogen (BUN), creatinine, Cystatin-C (CYT-C), neutrophil gelatinase-associated lipocalin (N-GAL) and Kidney Injury Molecule-1 (Kim-1) was recorded. Moreover, the treatment resulted in a remarkable decline in the serum levels of interleukin-18(IL-18), tumor necrosis factor- alpha (TNF-α), C reactive protein (CRP), BCL2 associated X protein (Bax), Factor-related Apoptosis (FAS) and the activity of Caspase-3 associated by an increase of B-cell CLL/lymphoma 2 (Bcl2) level. The results were confirmed with the histopathological examination. Kidney of irradiated showed glomerular atrophy, massive necrotic changes of expanded tubules with hyaline cast inside some tubules and apoptotic changes were recorded in some renal tubules. While irradiated rats treated with CUR and SLM exhibited marked preservation of the cellular structure of their kidney tissue. In conclusion, the combination of CUR and SLM could be more potent than a single agent on the biochemical and histological changes of the irradiated rat renal tissue.

Therapeutic effects of curcumin on sepsis and mechanisms of action: A systematic review of preclinical studies

Sepsis is a complex disease that begins with an infectious disorder and causes excessive immune responses. Curcumin is considered as an active component of turmeric that can improve the condition in sepsis due to its anti-inflammatory and antioxidant properties. PubMed, Embase, Google Scholar, Web of Science, and Scopus databases were searched. Searching was not limited to a specific publication period. Only English-language original articles, which had examined the effect of curcumin on sepsis, were included. At first, 1,098 articles were totally found, and 209 articles were selected after excluding duplicated data; 46 articles were remained due to the curcumin effects on sepsis. These included 23 in vitro studies and 23 animal studies. Our results showed that curcumin and various analogs of curcumin can have an inhibitory effect on sepsis-induced complications. Curcumin has the ability to inhibit the inflammatory, oxidative coagulation factors, and regulation of immune responses in sepsis. Despite the promising evidence of the therapeutic effects of curcumin on the sepsis complication, further studies seem necessary to investigate its effect and possible mechanisms of action in human studies.

Radiosensitizing effect of curcumin-loaded lipid nanoparticles in breast cancer cells

In breast cancer (BC) care, radiotherapy is considered an efficient treatment, prescribed both for controlling localized tumors or as a therapeutic option in case of inoperable, incompletely resected or recurrent tumors. However, approximately 90% of BC-related deaths are due to the metastatic tumor progression. Then, it is strongly desirable to improve tumor radiosensitivity using molecules with synergistic action. The main aim of this study is to develop curcumin-loaded solid nanoparticles (Cur-SLN) in order to increase curcumin bioavailability and to evaluate their radiosensitizing ability in comparison to free curcumin (free-Cur), by using an in vitro approach on BC cell lines. In addition, transcriptomic and metabolomic profiles, induced by Cur-SLN treatments, highlighted networks involved in this radiosensitization ability. The non tumorigenic MCF10A and the tumorigenic MCF7 and MDA-MB-231 BC cell lines were used. Curcumin-loaded solid nanoparticles were prepared using ethanolic precipitation and the loading capacity was evaluated by UV spectrophotometer analysis. Cell survival after treatments was evaluated by clonogenic assay. Dose–response curves were generated testing three concentrations of free-Cur and Cur-SLN in combination with increasing doses of IR (2–9 Gy). IC₅₀ value and Dose Modifying Factor (DMF) was measured to quantify the sensitivity to curcumin and to combined treatments. A multi-“omic” approach was used to explain the Cur-SLN radiosensitizer effect by microarray and metobolomic analysis. We have shown the efficacy of the Cur-SLN formulation as radiosensitizer on three BC cell lines. The DMFs values, calculated at the isoeffect of SF = 50%, showed that the Luminal A MCF7 resulted sensitive to the combined treatments using increasing concentration of vehicled curcumin Cur-SLN (DMF: 1,78 with 10 µM Cur-SLN.) Instead, triple negative MDA-MB-231 cells were more sensitive to free-Cur, although these cells also receive a radiosensitization effect by combination with Cur-SLN (DMF: 1.38 with 10 µM Cur-SLN). The Cur-SLN radiosensitizing function, evaluated by transcriptomic and metabolomic approach, revealed anti-oxidant and anti-tumor effects. Curcumin loaded- SLN can be suggested in future preclinical and clinical studies to test its concomitant use during radiotherapy treatments with the double implications of being a radiosensitizing molecule against cancer cells, with a protective role against IR side effects.

Genome-Wide Analysis Reveals Zinc Transporter ZIP9 Regulated by DNA Methylation Promotes Radiation-Induced Skin Fibrosis via the TGF-β Signaling Pathway

Radiation-induced skin fibrosis is a detrimental and chronic disorder that occurs after radiation exposure. DNA methylation has been characterized as an important regulatory mechanism of multiple pathological processes. In this study, we compared the genome-wide DNA methylation status in radiation-induced fibrotic skin and adjacent normal tissues of rats by methylated DNA immunoprecipitation sequencing. Radiation-induced fibrotic skin showed differentially methylated regions associated with 3,650 protein-coding genes, 72 microRNAs, 5,836 long noncoding RNAs and 3 piwi-interacting RNAs. By integrating the mRNA and methylation profiles, the zinc transporter SLC39A9/ZIP9 was investigated in greater detail. The protein level of ZIP9 was increased in irradiated skin tissues of humans, monkeys, and rats, especially in radiogenic fibrotic skin tissues. Radiation induced the demethylation of a CpG dinucleotide in exon 1 of ZIP9 that resulted in recruitment of the transcriptional factor Sp1 and increased ZIP9 expression. Overexpression of ZIP9 resulted in activation of the profibrotic transforming growth factor-β signaling pathway through protein kinase B in human fibroblasts. In addition, radiation-induced skin fibrosis was associated with increased zinc accumulation. The zinc chelator N,N,N',N'-tetrakis(2-pyridylmethyl)-1,2-ethylenediamine abrogated ZIP9-induced activation of the transforming growth factor-β signaling pathway and attenuated radiation-induced skin fibrosis in a rat model. In summary, our findings illustrate epigenetic regulation of ZIP9 and its critical role in promoting radiation-induced skin fibrosis.

Acute Skin Damage and Late Radiation-Induced Fibrosis and Inflammation in Murine Ears after High-Dose Irradiation

The use of different scoring systems for radiation-induced toxicity limits comparability between studies. We examined dose-dependent tissue alterations following hypofractionated X-ray irradiation and evaluated their use as scoring criteria. Four dose fractions (0, 5, 10, 20, 30 Gy/fraction) were applied daily to ear pinnae. Acute effects (ear thickness, erythema, desquamation) were monitored for 92 days after fraction 1. Late effects (chronic inflammation, fibrosis) and the presence of transforming growth factor beta 1 (TGFβ1)-expressing cells were quantified on day 92. The maximum ear thickness displayed a significant positive correlation with fractional dose. Increased ear thickness and erythema occurred simultaneously, followed by desquamation from day 10 onwards. A significant dose-dependency was observed for the severity of erythema, but not for desquamation. After 4 × 20 and 4 × 30 Gy, inflammation was significantly increased on day 92, whereas fibrosis and the abundance of TGFβ1-expressing cells were only marginally increased after 4 × 30 Gy. Ear thickness significantly correlated with the severity of inflammation and fibrosis on day 92, but not with the number of TGFβ1-expressing cells. Fibrosis correlated significantly with inflammation and fractional dose. In conclusion, the parameter of ear thickness can be used as an objective, numerical and dose-dependent quantification criterion to characterize the severity of acute toxicity and allow for the prediction of late effects.

Curcumin Mitigates Radiation-induced Lung Pneumonitis and Fibrosis in Rats

Radiation-induced lung injury is one of the most prominent factors that interfere with chest cancer radiotherapy, and poses a great threat to patients exposed to total body irradiation. Upregulation of pro-oxidant enzymes is one of the main mechanisms through which the late effects of ionizing radiation on lung injury can be exerted. Interleukin (IL)-4 and IL-13 are two important cytokines that have been proposed to be involved in this process. Through stimulation of dual oxidase 1 and 2 (DUOX 1 & 2), they induce chronic oxidative stress in irradiated tissues. In this study, we evaluated the effects of curcumin treatment on the regulation of IL-4 and IL-13, DUOX1 & 2 genes as well as the pathological changes developed by this treatment. Twenty male Wistar rats were divided into four groups: radiation only; curcumin only; radiation +curcumin; and control group with neither pharmacotherapy nor radiation. Curcumin was administered for 4 and 6 consecutive days before and after irradiation, respectively. Also, the chest area was irradiated with 15 Gy using a cobalt-60 gamma rays source. All rats were sacrificed 67 days after irradiation, followed by the assessment of the levels of IL-4 and IL-13; the expression of IL- 4 receptor-a1 (IL4Ra1), IL13Ra2, DUOX1 and DUOX2, and finally the histopathological changes were evaluated. Radiation led to the increased level of IL-4, while the level of IL-13 showed no change. QPCR results showed the upregulation of IL4Ra1, DUOX1 and DUOX2 following lung irradiation. Histopathological evaluation also showed a remarkable increase in pneumonitis and fibrosis. Treatment with curcumin downregulated the expression of IL-4, IL4Ra1, DUOX1 & 2. Furthermore, it could mitigate pneumonitis and fibrosis following lung irradiation. The late effects of radiation- induced lung injury may be due to the upregulation of DUOX1 & 2 genes. Curcumin, through modulation of these genes, may contribute to the protection against ionizing radiation.

Pharmacology of natural radioprotectors

Radiotherapy is one of the most efficient ways to treat cancer. However, deleterious effects, such as acute and chronic toxicities that reduce the quality of life, may result. Naturally occurring compounds have been shown to be non-toxic over wide dose ranges and are inexpensive and effective. Additionally, pharmacological strategies have been developed that use radioprotectors to inhibit radiation-induced toxicities. Currently available radioprotectors have several limitations, including toxicity. In this review, we present the mechanisms of proven radioprotectors, ranging from free radical scavenging (the best-known mechanism of radioprotection) to molecular-based radioprotection (e.g., upregulating expression of heat shock proteins). Finally, we discuss naturally occurring compounds with radioprotective properties in the context of these mechanisms.

Curcumin as an anti-inflammatory agent: Implications to radiotherapy and chemotherapy

Cancer is the second cause of death worldwide. Chemotherapy and radiotherapy are the most common modalities for the treatment of cancer. Experimental studies have shown that inflammation plays a central role in tumor resistance and the incidence of several side effects following both chemotherapy and radiotherapy. Inflammation resulting from radiotherapy and chemotherapy is responsible for adverse events such as dermatitis, mucositis, pneumonitis, fibrosis, and bone marrow toxicity. Chronic inflammation may also lead to the development of second cancer during years after treatment. A number of anti-inflammatory drugs such as nonsteroidal anti-inflammatory agents have been proposed to alleviate chronic inflammatory reactions after radiotherapy or chemotherapy. Curcumin is a well-documented herbal anti-inflammatory agents. Studies have proposed that curcumin can help management of inflammation during and after radiotherapy and chemotherapy. Curcumin targets various inflammatory mediators such as cyclooxygenase-2, inducible nitric oxide synthase, and nuclear factor κB (NF-κB), thereby attenuating the release of proinflammatory and profibrotic cytokines, and suppressing chronic production of free radicals, which culminates in the amelioration of tissue toxicity. Through modulation of NF-κB and its downstream signaling cascade, curcumin can also reduce angiogenesis, tumor growth, and metastasis. Low toxicity of curcumin is linked to its cytoprotective effects in normal tissues. This protective action along with the capacity of this phytochemical to sensitize tumor cells to radiotherapy and chemotherapy makes it a potential candidate for use as an adjuvant in cancer therapy. There is also evidence from clinical trials suggesting the potential utility of curcumin for acute inflammatory reactions during radiotherapy such as dermatitis and mucositis.

Evaluating the Protective Effect of a Combination of Curcumin and Selenium-L-Methionine on Radiation Induced Dual Oxidase Upregulation

Background: Epidemiological studies have shown an increased incidence of heart diseases among survivors of Chernobyl disaster as well as Hiroshima and Nagasaki atomic bomb explosion. Similar results were observed for lung and left breast cancer patients. Experimental studies have proposed the chronic upregulation of some pro-inflammatory and pro-fibrotic cytokines. Recent studies have shown that upregulation of pro-oxidant enzymes play a key role in the development of late effects of ionizing radiation such as fibrosis. Interleukin-4 (IL-4) and Interleukin-13 (IL-13) are two important cytokines that have shown ability to induce production of free radicals through dual oxidases (Duox) i.e. Duox1 and Duox2. In this study, we aimed to detect the expression of IL-4 receptor-a1 (IL-4Ra1), IL-13 receptor-a2 (IL-13Ra2), Duox1 and Duox2 genes following irradiation of rat’s heart. In addition, we evaluated the possible role of the combination of curcumin and selenium-L-methionine on the regulation of these genes. Methods: Twenty rats were divided into 4 groups as follows; G1: control; G2: treatment with the combination of curcumin and selenium-L-methionine; G3: radiation; G4: radiation plus treatment with the combination of curcumin and selenium-L-methionine. Rats were sacrificed 10 weeks after irradiation for detecting the expression of IL-4Ra1, IL-13Ra2, Duox1 and Duox2. Results: Results showed that exposure to ionizing radiation caused upregulation of IL-4Ra1 by more than 4-fold as well as Duox1 and Duox2 by more than 5-fold. However, results showed no detectable expression for IL-13Ra2. Treatment with the combination of curcumin and selenium-L-methionine could attenuate the upregulation of all genes. Conclusion: This study has shown that exposing rat’s heart tissues to radiation leads to chronic upregulation of IL-4Ra1, Duox1 and Duox2 as well as pro-oxidant enzymes. Treatment with the combination of curcumin and selenium-L-methionine showed ability to attenuate the upregulation of these genes.

Prevention from radiation damage by natural products

BACKGROUND

Radiotherapy is a mainstay of cancer treatment since decades. Ionizing radiation (IR) is used for destruction of cancer cells and shrinkage of tumors. However, the increase of radioresistance in cancer cells and radiation toxicity to normal tissues are severe concerns. The exposure to radiation generates intracellular reactive oxygen species (ROS), which leads to DNA damage by lipid peroxidation, removal of thiol groups from cellular and membrane proteins, strand breaks and base alterations.

HYPOTHESIS

Plants have to deal with radiation-induced damage (UV-light of sun, other natural radiation sources). Therefore, it is worth speculating that radioprotective mechanisms have evolved during evolution of life. We hypothesize that natural products from plants may also protect from radiation damage caused as adverse side effects of cancer radiotherapy.

METHODS

The basis of this systematic review, we searched the relevant literature in the PubMed database.

RESULTS

Flavonoids, such as genistein, epigallocatechin-3-gallate, epicatechin, apigenin and silibinin mainly act as antioxidant, free radical scavenging and anti-inflammatory compounds, thus, providing cytoprotection in addition to downregulation of several pro-inflammatory cytokines. Comparable effects have been found in phenylpropanoids, especially caffeic acid phenylethylester, curcumin, thymol and zingerone. Besides, resveratrol and quercetin are the most important cytoprotective polyphenols. Their radioprotective effects are mediated by a wide range of mechanisms mainly leading to direct or indirect reduction of cellular stress. Ascorbic acid is broadly used as antioxidant, but it has also shown activity in reducing cellular damage after irradiation mainly due to its antioxidant capabilities. The metal ion chelator, gallic acid, represents another natural product attenuating cellular damage caused by radiation.

CONCLUSIONS

Some secondary metabolites from plants reveal radioprotective features against cellular damage caused by irradiation. These results warrant further analysis to develop phytochemicals as radioprotectors for clinical use.

Anthocyanins from black soybean seed coat prevent radiation-induced skin fibrosis by downregulating TGF-β and Smad3 expression

The aim of this study was to evaluate the protective effects of anthocyanins from the black soybean seed coat against radiation injury in dermal fibroblasts and mouse skin. Dermal fibroblasts treated with 50 and 100 µg/mL anthocyanins were irradiated with single doses of 20 Gy. Cell viability, intracellular reactive oxygen species (ROS) production, and mRNA expression were measured. A total of 60 mice were used for an in vivo study. A dose of 100 µg/mL anthocyanins was administered daily for 5 days before or after radiation therapy. Following irradiation (45 Gy), mice were inspected for gross pathology twice per wk for 8 weeks. At 4 and 8 weeks post-irradiation, dorsal skin was harvested for histopathologic examination and protein isolation. In dermal fibroblasts, treatment with 50 and 100 µg/mL anthocyanins significantly reduced radiation-induced apoptosis at 72 h and intracellular reactive oxygen species generation at 48 h. Furthermore, 100 µg/mL anthocyanins markedly decreased Smad3 mRNA expression and increased Smad7 mRNA expression at 72 h post-irradiation. In mice, treatment with 100 µg/mL anthocyanins resulted in a significant reduction in the level of skin injury, epidermal thickness, and collagen deposition after irradiation. Treatment with 100 µg/mL anthocyanins significantly decreased the number of α-SMA-, TGF-β-, and Smad3-positive cells after irradiation. Our study demonstrated that black soybean anthocyanins inhibited radiation-induced fibrosis by downregulating TGF-β and Smad3 expression. Therefore, anthocyanins may be a safe and effective candidate for the prevention of radiation-induced skin fibrosis.

Oral curcumin for radiation dermatitis: a URCC NCORP study of 686 breast cancer patients

PURPOSE

Despite advances in medical technology, radiation dermatitis occurs in 95% of patients receiving radiation therapy (RT) for cancer. Currently, there is no standard and effective treatment for the prevention or control of radiation dermatitis. The goal of the study was to determine the efficacy of oral curcumin, one of the biologically active components in turmeric, at reducing radiation dermatitis severity (RDS) at the end of RT, using the RDS scale, compared to placebo.

METHODS

This was a multisite, randomized, double-blinded, placebo-controlled trial of 686 breast cancer patients. Patients took four 500-mg capsules of placebo or curcumin three times daily throughout their prescribed course of RT until 1 week post-RT.

RESULTS

A total of 686 patients were included in the final analyses (87.5% white females, mean age = 58). Linear mixed-model analyses demonstrated that curcumin did not reduce radiation dermatitis severity at the end of RT compared to placebo (B (95% CI) = 0.044 (- 0.101, 0.188), p = 0.552). Fewer curcumin patients with RDS > 3.0 suggested a trend toward reduced severity (7.4 vs. 12.9%, p = 0.082). Patient-reported changes in pain, symptoms, and quality of life were not statistically significant between arms.

CONCLUSIONS

Oral curcumin did not significantly reduce radiation dermatitis severity compared to placebo. The skin rating variation and broad eligibility criteria could not account for the undetectable therapeutic effect. An objective measure for radiation dermatitis severity and further exploration for an effective treatment for radiation dermatitis is warranted.

Nanocurcumin-Mediated Down-Regulation of Telomerase Via Stimulating TGFβ1 Signaling Pathway in Hepatocellular Carcinoma Cells

Background

Curcumin, extracted from turmeric, represents enormous potential to serve as an anticancer agent. Telomerase is viewed as a prominent molecular target of curcumin, and Transforming growth factor-β1 (TGFβ1) has proven to be a major inhibitory signaling pathway for telomerase activity. In the current study, we aimed to explore suppressive effects of nanocurcumin on telomerase expression through TGFβ1 pathway in a hepatocellular carcinoma cell line (Huh7).

Methods

MTT assay was used to determine the effect of nonocurcumin on viability of Huh7 cells. RT-PCR was used to analyze the gene expression patterns.

Results

MTT assay revealed that nanocurcumin acts in a dose- and time-dependent manner to diminish the cell viability. RT-PCR analysis indicated that nanocurcumin results in augmentation of TGFβ1 72 hours post treatment and leads to the reduction of telomerase expression 48 and 72 hours post exposure. Also, up-regulation of Smad3 and E2F1 and down-regulation of Smad7 confirmed the effect of nanocurcumin on intermediate components of TGFβ1 pathway. Furthermore, transfection of the proximal promoter of telomerase triggered a significant reduction in luciferase activity.

Conclusion

The data from the present study lead us to develop a deeper understanding of the mechanisms underlying nanocurcumin-mediated regulation of telomerase expression, thereby presenting a new perspective to the landscape of using nanocurcumin as a cancer-oriented therapeutic agent.

Topical Treatment of Skin Injury Inflicted in Mice by X-Ray Irradiation

BACKGROUND/AIMS

There is no treatment, without side effects, efficiently preventing or curing skin burns, caused by radiotherapy. A new experimental topical treatment protocol was assessed in mice receiving orthovoltage X-rays at an equivalent dose to that applied to human breast cancer patients in conventional radiotherapy.

METHODS

SKH-HR2 female hairless mice were irradiated on their dorsum with a total dose of 4,300 cGy during a 1-month period (20 fractions). The treatment group received a combination of 3 topical products, an oil-in-water cream, a gel containing Pinus halepensis bark aqueous extract, and an ointment containing olive oil extract of the marine isopod Ceratothoa oestroides. The positive control group was treated with a conventionally used commercial gel, whereas the negative control group did not receive any topical treatment. Skin alterations were evaluated by macroscopic examinations, measurements of transepidermal water loss (TEWL), melanin content, erythema intensity, hydration, and histopathology assessment.

RESULTS

Sixty days after radiation, TEWL and hydration values were abnormal and elements of acute, chronic, and granulomatous inflammation were present in all cases. The severest damage was detected in the deeper dermis. Treatment showed a comparatively beneficial effect on chronic and granulomatous inflammation while positive control was beneficial on acute inflammation.

CONCLUSION

Skin anti-inflammatory treatment was the most effective but must be applied for several months. Further preclinical studies should be conducted, assimilating a human cancer radiation therapeutic schema with the aim of optimizing skin inflammation treatment.

The Role of FABP5 in Radiation-Induced Human Skin Fibrosis

Radiation-induced skin fibrosis is a detrimental and chronic disorder that occurs after radiation exposure. The molecular changes underlying the pathogenesis of radiation-induced fibrosis of human skin have not been extensively reported. Technical advances in proteomics have enabled exploration of the biomarkers and molecular pathogenesis of radiation-induced skin fibrosis, with the potential to broaden our understanding of this disease. In this study, we compared protein expression in radiation-induced fibrotic human skin and adjacent normal tissues using iTRAQ-based proteomics technology. We identified 186 preferentially expressed proteins (53 upregulated and 133 downregulated) between radiogenic fibrotic and normal skin tissues. The differentially expressed proteins included keratins (KRT5, KRT6A, KRT16 and KRT17), caspase-14, fatty acid-binding protein 5 (FABP5), SLC2A14 and resistin. Through bioinformatic analysis of the proximal promoters, common motifs and corresponding transcriptional factors were identified that associate with the dysregulated proteins, including PAX5, TBX1, CLOCK and AP2D. In particular, FABP5 (2.15-fold increase in fibrotic skin tissues), a transporter of hydrophobic fatty acids, was investigated in greater detail. Immunohistochemistry confirmed that the protein level of FABP5 was increased in fibrotic human skin tissues, especially in the epidermis. Overexpression of FABP5 resulted in nuclear translocation of SMAD2 and significant activation of the profibrotic TGF-β signaling pathway in human fibroblast WS1 cells. Moreover, exogenous FABP5 (FABP5-EGFP) could be incorporated by skin cells and intensify TGF-β signaling, indicating a communication between the microenvironment and skin fibrosis. Taken together, our findings illustrate the molecular changes during radiation-induced human skin fibrosis and the critical role of FABP5 in activating the TGF-β signaling pathway.

Curcumin: A natural modulator of immune cells in systemic lupus erythematosus

Curcumin is a polyphenol natural product isolated from turmeric, interacting with different cellular and molecular targets and, consequently, showing a wide range of pharmacological effects. Recent preclinical and clinical trials have revealed immunomodulatory properties of curcumin that arise from its effects on immune cells and mediators involved in the immune response, such as various T-lymphocyte subsets and dendritic cells, as well as different inflammatory cytokines. Systemic lupus erythematosus (SLE) is an inflammatory, chronic autoimmune-mediated disease characterized by the presence of autoantibodies, deposition of immune complexes in various organs, recruitment of autoreactive and inflammatory T cells, and excessive levels of plasma proinflammatory cytokines. The function and numbers of dendritic cells and T cell subsets, such as T helper 1 (Th1), Th17, and regulatory T cells have been found to be significantly altered in SLE. In the present report, we reviewed the results of in vitro, experimental (pre-clinical), and clinical studies pertaining to the modulatory effects that curcumin produces on the function and numbers of dendritic cells and T cell subsets, as well as relevant cytokines that participate in SLE.

A review of radiation countermeasures focusing on injury-specific medicinals and regulatory approval status: part III. Countermeasures under early stages of development along with 'standard of care' medicinal and procedures not requiring regulatory approval for use

PURPOSE

Terrorist attacks, with their intent to maximize psychological and economic damage as well as inflicting sickness and death on given targeted populations, are an ever-growing worldwide concern in government and public sectors as they become more frequent, violent, and sensational. If given the chance, it is likely that terrorists will use radiological or nuclear weapons. To thwart these sinister efforts, both physical and medical countermeasures against these weapons are currently being researched and developed so that they can be utilized by the first responders, military, and medical providers alike. This is the third article of a three-part series in which we have reviewed additional radiation countermeasures that are currently under early preclinical phases of development using largely animal models and have listed and discussed clinical support measures, including agents used for radiation-induced emesis, as well as countermeasures not requiring Food and Drug Administration approval.

CONCLUSIONS

Despite the significant progress that has been made in this area during the last several years, additional effort is needed in order to push promising new agents, currently under development, through the regulatory pipeline. This pipeline for new promising drugs appears to be unreasonably slow and cumbersome; possible reasons for this inefficiency are briefly discussed. Significant and continued effort needs to be afforded to this research and development area, as to date, there is no approved radioprotector that can be administered prior to high dose radiation exposure. This represents a very significant, unmet medical need and a significant security issue. A large number of agents with potential to interact with different biological targets are under development. In the next few years, several additional radiation countermeasures will likely receive Food and Drug Administration approval, increasing treatment options for victims exposed to unwanted ionizing irradiation.

A review of radiation countermeasures focusing on injury-specific medicinals and regulatory approval status: part I. Radiation sub-syndromes, animal models and FDA-approved countermeasures

PURPOSE

The increasing global risk of nuclear and radiological accidents or attacks has driven renewed research interest in developing medical countermeasures to potentially injurious exposures to acute irradiation. Clinical symptoms and signs of a developing acute radiation injury, i.e. the acute radiation syndrome, are grouped into three sub-syndromes named after the dominant organ system affected, namely the hematopoietic, gastrointestinal, and neurovascular systems. The availability of safe and effective countermeasures against the above threats currently represents a significant unmet medical need. This is the first article within a three-part series covering the nature of the radiation sub-syndromes, various animal models for radiation countermeasure development, and the agents currently approved by the United States Food and Drug Administration for countering the medical consequences of several of these prominent radiation exposure-associated syndromes.

CONCLUSIONS

From the U.S. and global perspectives, biomedical research concerning medical countermeasure development is quite robust, largely due to increased government funding following the 9/11 incidence and subsequent rise of terrorist-associated threats. A wide spectrum of radiation countermeasures for specific types of radiation injuries is currently under investigation. However, only a few radiation countermeasures have been fully approved by regulatory agencies for human use during radiological/nuclear contingencies. Additional research effort, with additional funding, clearly will be needed in order to fill this significant, unmet medical health problem.

Sandalwood Oil and Turmeric-Based Cream Prevents Ionizing Radiation-Induced Dermatitis in Breast Cancer Patients: Clinical Study

Background: The primary objective of this study was to ascertain the benefit of Vicco turmeric Ayurvedic cream (VTC; Vicco Laboratories, Mumbai, India) sandalwood oil and turmeric-based cream in preventing radiodermatitis in women undergoing curative radiotherapy for their breast cancer. Methods and Materials: The study was an investigator-blinded randomized study with Johnsons Baby Oil (JBO; Johnson & Johnson Ltd., Baddi, India) as a comparator, administered daily from the start of radiation therapy for 5 weeks in women receiving breast radiation therapy, 50 Gy in 2 Gy fractions daily for 5 weeks. The endpoints were to ascertain the delay in the appearance and the degree of severity of dermatitis throughout the study period in accordance to the Therapy Oncology Group (RTOG) score. Results: The results indicated that the topical application of VTC delayed and mitigated the radiodermatitis. When compared to the Johnson’s Baby Oil, a significant decrease (p = 0.025) in the incidence of grade 1 was seen at week two, and also in grade 2 and 3 at week 3 (p = 0.003) and week 4 (p = 0.02), respectively, in the VTC cohort. A concomitant decrease in the average severity was also observed at week 2 (p = 0.02), week 3 (p = 0.05) and week 4 (p = 0.03). Conclusions: The results indicate that VTC cream significantly reduces radiation dermatitis when applied to the breast during and after radiation therapy. The result of this study indicates the beneficial effects. Double blind randomized control studies are required to further confirm the beneficial effects of VTC in mitigating radiodermatitis is people undergoing radiation treatment for their cancer.

Therapeutic potential of novel formulated forms of curcumin in the treatment of breast cancer by the targeting of cellular and physiological dysregulated pathways

Breast cancer is among the most important causes of cancer related death in women. There is a need for novel agents for targeting key signaling pathways to either improve the efficacy of the current therapy, or reduce toxicity. There is some evidence that curcumin may have antitumor activity in breast cancer. Several clinical trials have investigated its activity in patients with breast cancer, including a recent trial in breast cancer patients receiving radiotherapy, in whom it was shown that curcumin reduced the severity of radiation dermatitis, although it is associated with low bioavailability. Several approaches have been developed to increase its absorption rate (e.g., nano crystals, liposomes, polymers, and micelles) and co-delivery of curcumin with adjuvants as well as different conjugation to enhance its bioavailability. In particular, micro-emulsions is an option for transdermal curcumin delivery, which has been reported to increase its absorption. Lipid-based nano-micelles is another approach to enhance curcumin absorption via gastrointestinal tract, while polymer-based nano-formulations (e.g., poly D, L-lactic-co-glycolic [PLGA]) allows the release of curcumin at a sustained level. This review summarizes the current data of the therapeutic potential of novel formulations of curcumin with particular emphasis on recent preclinical and clinical studies in the treatment of breast cancer.

Acute radiation dermatitis in breast cancer patients: challenges and solutions

Nearly all women who receive radiotherapy (RT) for breast cancer experience some degree of radiation dermatitis. However, evidence describing the appropriate management of radiation dermatitis is often lacking or contradictory. Here, we summarize the available literature regarding radiation dermatitis causes, the presentation and timing of symptoms, methods for dermatitis assessment and prevention, and review evidence-based management strategies.

Therapeutic effect of topical application of curcumin during treatment of radiation burns in a mini-pig model

Curcumin protects the skin against radiation-induced epidermal damage and prevents morphological changes induced by irradiation skin, thereby maintaining the epidermal thickness and cell density of basal layers. In this study, the effects of topical curcumin treatment on radiation burns were evaluated in a mini-pig model. Histological and clinical changes were observed five weeks after radiation exposure to the back (⁶⁰Co gamma-radiation, 50 Gy). Curcumin was applied topically to irradiated skin (200 mg/cm²) twice a day for 35 days. Curcumin application decreased the epithelial desquamation after irradiation. Additionally, when compared to the vehicle-treated group, the curcumin-treated group showed reduced expression of cyclooxygenase-2 and nuclear factor-kappaB. Furthermore, irradiation prolonged healing of biopsy wounds in the exposed area, whereas curcumin treatment stimulated wound healing. These results suggest that curcumin can improve epithelial cell survival and recovery in the skin and therefore be used to treat radiation burns.

Current Status of Targeted Radioprotection and Radiation Injury Mitigation and Treatment Agents: A Critical Review of the Literature

As more cancer patients survive their disease, concerns about radiation therapy-induced side effects have increased. The concept of radioprotection and radiation injury mitigation and treatment offers the possibility to enhance the therapeutic ratio of radiation therapy by limiting radiation therapy-induced normal tissue injury without compromising its antitumor effect. Advances in the understanding of the underlying mechanisms of radiation toxicity have stimulated radiation oncologists to target these pathways across different organ systems. These generalized radiation injury mechanisms include production of free radicals such as superoxides, activation of inflammatory pathways, and vascular endothelial dysfunction leading to tissue hypoxia. There is a significant body of literature evaluating the effectiveness of various treatments in preventing, mitigating, or treating radiation-induced normal tissue injury. Whereas some reviews have focused on a specific disease site or agent, this critical review focuses on a mechanistic classification of activity and assesses multiple agents across different disease sites. The classification of agents used herein further offers a useful framework to organize the multitude of treatments that have been studied. Many commonly available treatments have demonstrated benefit in prevention, mitigation, and/or treatment of radiation toxicity and warrant further investigation. These drug-based approaches to radioprotection and radiation injury mitigation and treatment represent an important method of making radiation therapy safer.

Chronic radiation-induced dermatitis: challenges and solutions

Chronic radiation dermatitis is a late side effect of skin irradiation, which may deteriorate patients’ quality of life. There is a lack of precise data about its incidence; however, several risk factors may predispose to the development of this condition. It includes radiotherapy dose, fractionation, technique, concurrent systemic therapy, comorbidities, and personal and genetic factors. Chronic radiation dermatitis is mostly caused by the imbalance of proinflammatory and profibrotic cytokines. Clinical manifestation includes changes in skin appearance, wounds, ulcerations, necrosis, fibrosis, and secondary cancers. The most severe complication of irradiation is extensive radiation-induced fibrosis (RIF). RIF can manifest in many ways, such as skin induration and retraction, lymphedema or restriction of joint motion. Diagnosis of chronic radiation dermatitis is usually made by clinical examination. In case of unclear clinical manifestation, a biopsy and histopathological examination are recommended to exclude secondary malignancy. The most effective prophylaxis of chronic radiation dermatitis is the use of proper radiation therapy techniques to avoid unnecessary irradiation of healthy skin. Treatment of chronic radiation dermatitis is demanding. The majority of the interventions are based only on clinical practice. Telangiectasia may be treated with pulse dye laser therapy. Chronic postirradiation wounds need special dressings. In case of necrosis or severe ulceration, surgical intervention may be considered. Management of RIF should be complex. Available methods are rehabilitative care, pharmacotherapy, hyperbaric oxygen therapy, and laser therapy. Future challenges include the assessment of late skin toxicity in modern irradiation techniques. Special attention should be paid on genomics and radiomics that allow scientists and clinicians to select patients who are at risk of the development of chronic radiation dermatitis. Novel treatment methods and clinical trials are strongly needed to provide more efficacious therapies.