Investigations of antioxidant-mediated protection and mitigation of radiation-induced DNA damage and lipid peroxidation in murine skin

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.

Effects of low-dose radiation on human blood components after in vitro exposure to gamma radiation from 137Cs radioactivity

This current study was designed to determine the effects of in vitro exposure to radioactive cesium-137 on human blood components. Whole blood samples were given a radiation dose of 0.02, 0.05, 0.1, 0.2, and 0.3 mGy of gamma radiation using a ¹³⁷Cs radioactive standard source. The whole blood samples that were exposed to 0 mGy served as sham-controls. The spectrofluoroscopic technique was used to determine the autofluorescence spectrum of protein in plasma or red blood cells by using excitation wavelength and range of emission wavelengths at 280 nm and 300-550 nm, respectively. The hemolysis of red blood cells was evaluated by determination of the release of hemoglobin from the red blood cells to the supernatant. Complete blood counts were also determined in whole blood. The results showed that there was no change in the ratio of fluorescence emission intensity at 340 nm of wavelength of protein extract from irradiated whole blood or red blood cells compared to the corresponding non-irradiated control. The hemolysis value did not change in irradiated whole blood when compared to the corresponding non-irradiated group. In addition, complete blood count values in irradiated groups did not differ from non-irradiated group. These current results suggested that there were no harmful effects of the low-dose gamma radiation from radioactive ¹³⁷Cs on blood components when human whole blood was exposed to gamma radiation in an in vitro condition.

Inter-agency perspective: Translating advances in biomarker discovery and medical countermeasures development between terrestrial and space radiation environments

Over the past 20+ years, the U.S. Government has made significant strides in establishing research funding and initiating a portfolio consisting of subject matter experts on radiation-induced biological effects in normal tissues. Research supported by the National Cancer Institute (NCI) provided much of the early findings on identifying cellular pathways involved in radiation injuries, due to the need to push the boundaries to kill tumor cells while minimizing damage to intervening normal tissues. By protecting normal tissue surrounding the tumors, physicians can deliver a higher radiation dose to tumors and reduce adverse effects related to the treatment. Initially relying on this critical NCI research, the National Institute of Allergy and Infectious Diseases (NIAID), first tasked with developing radiation medical countermeasures in 2004, has provided bridge funding to move basic research toward advanced development and translation. The goal of the NIAID program is to fund approaches that can one day be employed to protect civilian populations during a radiological or nuclear incident. In addition, with the reality of long-term space flights and the possibility of radiation exposures to both acute, high-intensity, and chronic lower-dose levels, the National Aeronautics and Space Administration (NASA) has identified requirements to discover and develop radioprotectors and mitigators to protect their astronauts during space missions. In sustained partnership with sister agencies, these three organizations must continue to leverage funding and findings in their overlapping research areas to accelerate biomarker identification and product development to help safeguard these different and yet undeniably similar human populations - cancer patients, public citizens, and astronauts.

Internalized Nanoceria Modify the Radiation-Sensitivity Profile of MDA MB231 Breast Carcinoma Cells

Owing to its unique redox properties, cerium oxide (nanoceria) nanoparticles have been shown to confer either radiosensitization or radioprotection to human cells. We investigated nanoceria's ability to modify cellular health and reactive oxygen species (ROS) at various absorbed doses (Gray) of ionizing radiation in MDA-MB231 breast carcinoma cells. We used transmission electron microscopy to visualize the uptake and compartmental localization of nanoceria within cells at various treatment concentrations. The effects on apoptosis and other cellular health parameters were assessed using confocal fluorescence imaging and flow cytometry without and with various absorbed doses of ionizing radiation, along with intracellular ROS levels. Our results showed that nanoceria were taken up into cells mainly by macropinocytosis and segregated into concentration-dependent large aggregates in macropinosomes. Confocal imaging and flow cytometry data showed an overall decrease in apoptotic cell populations in proportion to increasing nanoparticle concentrations. This increase in cellular health was observed with a corresponding reduction in ROS at all tested absorbed doses. Moreover, this effect appeared pronounced at lower doses compared to unirradiated or untreated populations. In conclusion, internalized nanoceria confers radioprotection with a corresponding decrease in ROS in MDA-MB231 cells, and this property confers significant perils and opportunities when utilized in the context of radiotherapy.

Different responses of normal cells (red blood cells) and cancer cells (K562 and K562/Dox cells) to low-dose 137Cs gamma-rays

High-dose radiation is deleterious to cells or tissues. However, the health risks of exposure to low-dose radiation remain unclear. The present study aimed to investigate the biological responses of low-dose gamma-ray in vitro exposure to normal red blood cells (RBCs) and erythroleukemia (K562 and K562/Dox) cancer cells. Cells were given a low dose of 0.03, 0.05 and 0.1 mGy of ¹³⁷Cs gamma-rays (at a dose rate of 0.001 Gy/min) under in vitro conditions. Cells exposed to 0 Gy served as controls. Hemolysis and reactive oxygen species (ROS) were measured in exposed RBCs following exposure to low-dose gamma-rays. In addition, complete blood count (CBC) parameters were determined in irradiated whole blood. For irradiated K562 and K562/Dox cancer cells, ROS and mitochondrial activity were measured at 0, 30, 60 and 120 post-irradiation times. The results showed no change in the percentage of ROS and hemolysis in irradiated RBCs. The data indicated no perturbation in the CBC parameters in irradiated whole blood. By contrast, statistically significant dose-dependent increases in the percentage of ROS and decreases in the mitochondrial activity in the K562 and K562/Dox cancer cells were observed from 0 min up to 120 min post-irradiation. These findings concluded that there were differences in biological responses in normal cells (RBCs) and cancer cells (K562 and K562/Dox) to low-dose gamma-rays when cells were irradiated under in vitro conditions.

Pursuing the Elixir of Life: In Vivo Antioxidative Effects of Manganosalen Complexes

Manganosalen complexes are coordination compounds that possess a chelating salen-type ligand, a class of bis-Schiff bases obtained by condensation of salicylaldehyde and a diamine. They may act as catalytic antioxidants mimicking both the structure and the reactivity of the native antioxidant enzymes active site. Thus, manganosalen complexes have been shown to exhibit superoxide dismutase, catalase, and glutathione peroxidase activities, and they could potentially facilitate the scavenging of excess reactive oxygen species (ROS), thereby restoring the redox balance in damaged cells and organs. Initial catalytic studies compared the potency of these compounds as antioxidants in terms of rate constants of the chemical reactivity against ROS, giving catalytic values approaching and even exceeding that of the native antioxidative enzymes. Although most of these catalytic studies lack of biological relevance, subsequent in vitro studies have confirmed the efficiency of many manganosalen complexes in oxidative stress models. These synthetic catalytic scavengers, cheaper than natural antioxidants, have accordingly attracted intensive attention for the therapy of ROS-mediated injuries. The aim of this review is to focus on in vivo studies performed on manganosalen complexes and their activity on the treatment of several pathological disorders associated with oxidative damage. These disorders, ranging from the prevention of fetal malformations to the extension of lifespan, include neurodegenerative, inflammatory, and cardiovascular diseases; tissue injury; and other damages related to the liver, kidney, or lungs.

Quantitative proteomics reveals mitochondrial respiratory chain as a dominant target for carbon ion radiation: Delayed reactive oxygen species generation caused DNA damage

Heavy ion radiotherapy has shown great promise for cancer therapy. Understanding the cellular response mechanism to heavy ion radiation is required to explore measures of overcoming devastating side effects. Here, we performed a quantitative proteomic analysis to investigate the mechanism of carbon ion irradiation on human AHH-1 lymphoblastoid cells. We identified 4602 proteins and quantified 4569 proteins showing high coverage in the mitochondria. Data are available via ProteomeXchange with identifier PXD008351. After stringent filtering, 290 proteins were found to be significantly up-regulated and 16 proteins were down-regulated. Functional analysis revealed that these up-regulated proteins were enriched in the process of DNA damage repair, mitochondrial ribosome, and particularly mitochondrial respiratory chain, accounting for approximately 50% of the accumulated proteins. Bioinformatics and functional analysis demonstrated that these up-regulated mitochondrial respiratory chain proteins enhanced ATP production and simultaneously reactive oxygen species release. More importantly, increased reactive oxygen species led to secondary organelle injury and lagged DNA double-strand breaks. Consistently, the expression of antioxidant enzymes was up-regulated for free radical scavenging. The mechanism of lagged secondary injury originated from disturbances in the mitochondrial respiratory chain. Our results provided a novel target for cell self-repair against heavy ion radiation-induced cellular damage.

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.

Radioprotective agents to prevent cellular damage due to ionizing radiation

Medical imaging has become a central component of patient care to ensure early and accurate diagnosis. Unfortunately, many imaging modalities use ionizing radiation to generate images. Ionizing radiation even in low doses can cause direct DNA damage and generate reactive oxygen species and free radicals, leading to DNA, protein, and lipid membrane damage. This cell damage can lead to apoptosis, necrosis, teratogenesis, or carcinogenesis. As many as 2% of cancers (and an associated 15,000 deaths annually) can be linked to computed tomography exposure alone. Radioprotective agents have been investigated using various models including cells, animals, and recently humans. The data suggest that radioprotective agents working through a variety of mechanisms have the potential to decrease free radical damage produced by ionizing radiation. Radioprotective agents may be useful as an adjunct to medical imaging to reduced patient morbidity and mortality due to ionizing radiation exposure. Some radioprotective agents can be found in high quantities in antioxidant rich foods, suggesting that a specific diet recommendation could be beneficial in radioprotection.

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.

Effects of traditional oriental medicines as anti-cytotoxic agents in radiotherapy

The primary goal of radiotherapy in oncology is to enhance the efficacy of tumor cell death while decreasing damage to surrounding normal cells. Positive therapeutic outcomes may be accomplished by improved targeting, precisely targeting tumor cells or protecting normal cells against radiation-induced damage. The potential for antioxidants to decrease normal tissue damage induced by radiation has been investigated in animal models for a number of decades. In attempts for radioprotection, certain synthetic chemicals are suggested as antioxidants and normal tissue protectors against radiation-induced damage, but they have exhibited limitations in pharmacological application due to undesirable effects and high toxicities at clinical doses. The present review focuses on the radioprotective efficacy of traditional oriental medicines with the advantage of low toxicity at pharmacological doses and how such treatments may influence various harmful effects induced by radiation in vitro and in vivo. In addition, medicinal plants and their active constituents with biological activities that may be associated with alleviation of radiation-induced damage through antioxidant, anti-inflammatory, wound healing and immunostimulatory properties are discussed.

Effects of Medical Diagnostic Low-dose X Rays on Human Lymphocytes: Mitochondrial Membrane Potential, Apoptosis and Cell Cycle

Low-dose radiation is widely used across the world for the diagnosis of many diseases by means of a variety of imaging technologies. However, the harmful effects of exposure to low-dose radiation during medical examination remain controversial. The authors studied the effects of medical diagnostic low-dose x rays (i.e., 0.03, 0.05, or 0.1 mGy) after an in vitro exposure of human lymphocytes. Cells with no irradiation served as the non-irradiated control group. Three biological indicators were used to determine the effects of medical diagnostic low-dose x rays at 4, 8, 24, 48, and 72 h post-irradiation. These biological endpoints were mitochondrial membrane potential (ΔΨm), cell cycle, and apoptosis. Results indicated no changes in the ΔΨm, number of apoptotic cells, and cell cycle in lymphocytes exposed to these low doses of radiation, as compared to the corresponding non-irradiated lymphocytes at all harvest time-points. These results suggested that there were no harmful effects of the diagnostic low-dose x rays when human lymphocytes were exposed in an in vitro condition.

Folic acid enhances the apoptotic and genotoxic activity of carboplatin in HeLa cell line

In human tumor cells, experimental and clinical evidence indicates that some factors involved in signal transduction and cell growth can also modulate the response to chemotherapeutic treatment. The aim of the present study was to investigate the role of folic acid (FA) as a modulator of carboplatin (CBDCA) activity. Genotoxicity and cytotoxicity induced by CBDCA alone and in combination with FA were assessed in cultured HeLa cells. We used comet assay, mitotic index analysis, MTT and NR assays, cytokinesis-block micronucleus cytome assay and annexin V-IP as different cytotoxicity and genotoxicity approaches for human cervical carcinoma cell line studies. The results showed that addition of 900nM FA together with 40.4mM CBDCA enhanced the activity of the platinum compound, increasing its effect on cell death by nearly 20%, as evidenced by the MTT and NR assays. Moreover, not only higher levels of DNA and chromosomal damage were reached but also the number of necrotic and apoptotic cells were significantly increased when cell cultures were treated with the combined procedure. This situation opens the possibility to explore the use of FA in platinum-based chemotherapy protocols to reduce the platinum doses for patient treatment and decrease the chance of developing the known side effects without losing biological activity.

Curcumin confers protection to irradiated THP-1 cells while its nanoformulation sensitizes these cells via apoptosis induction

Protection against ionizing radiation (IR) and sensitization of cancer cells to IR are apparently contrasting phenomena. However, curcumin takes on these contrasting roles leading to either protection or enhanced apoptosis in different irradiated cells. Here we studied whether pretreatment with free curcumin or a novel dendrosomal nanoformulation of curcumin (DNC) could exert protective/sensitizing effects on irradiated THP-1 leukemia cells. We employed assays including MTT viability, clonogenic survival, DNA fragmentation, PI/Annexin V flow cytometry, antioxidant system (ROS, TBARS for lipid peroxidation, 8-OHdG and γH2AX for DNA damage, glutathione, CAT and GPx activity, enzymes gene expression), ELISA (NF-κB and Nrf2 binding, TNF-α release), caspase assay, siRNA silencing of caspase-3, and western blotting to illustrate the observed protective role of curcumin in comparison with the opposite sensitizing role of its nanoformulation at a similar 10 μM concentration. The in vivo relevance of this concentration was determined via intraperitoneal administration in mice. Curcumin significantly enhanced the antioxidant defense, while DNC induced apoptosis and reduced viability as well as survival of irradiated THP-1 cells. Nrf2 binding showed an early rise and fall in DNC-treated cells, despite a gradual increase in curcumin-treated cells. We also demonstrated that DNC induced apoptosis in THP-1 cells via caspase-3 activation; whereas in combination with radiation, DNC alternatively employed a caspase-independent apoptosis pathway involving cytochrome c release from mitochondria.

Induction of chronic oxidative stress, chronic inflammation and aberrant patterns of DNA methylation in the liver of titanium-exposed CBA/CaJ mice

PURPOSE

To investigate the biological effects of titanium ((48)Ti, one of the important heavy ions found in space) in the liver of exposed-mice.

MATERIALS AND METHODS

We gave adult male CBA/CaJ mice a whole-body exposure to a total dose of 0, 0.1, 0.25 or 0.5 Gy of (48)Ti ions. The liver was collected at 1 week, 1 month, and 6 months post-irradiation (five mice per treatment-group at each harvest-time). Three biological endpoints were used for evaluating the effects of (48)Ti ions: Oxidative-stress, inflammatory responses, and DNA-methylation (5-methylcytosine and 5-hydroxymethylcytosine).

RESULTS

Our data clearly demonstrated dose-dependent increases in oxidative stress and inflammatory responses in the liver of exposed mice at all time-points (Analysis of Variance or ANOVA, p < 0.05). Significant dose-dependent increases in the levels of 5-methylcytosine were detected at 1 week and 1 month (ANOVA, p < 0.05). At 6 months post-irradiation, a significant increase in the level of 5-methylcytosine was found only in 0.5-Gy-(48)Ti-ion-exposed mice. In contrast, dose-dependent decreases in 5-hydroxymethylcytosine levels were found in the liver of exposed mice (ANOVA, p < 0.05) at all time-points.

CONCLUSIONS

Chronic oxidative-stress, chronic inflammation, and persistent aberrant DNA-methylation occurred in the liver of (48)Ti-exposed mice. Hence, exposure to (48)Ti ions in space may pose health risks.

Curcumin Stimulates the Antioxidant Mechanisms in Mouse Skin Exposed to Fractionated γ-Irradiation

Fractionated irradiation is one of the important radiotherapy regimens to treat different types of neoplasia. Despite of the immense therapeutic gains accrued by delivering fractionated irradiation to tumors, the radiation burden on skin increases significantly. Low doses of irradiation to skin adversely affect its molecular and metabolic status. The use of antioxidant/s may help to alleviate the radiation-induced changes in the skin and allow delivering a higher dose of radiation to attain better therapeutic gains. Curcumin is an antioxidant and a free radical scavenging dietary supplement, commonly used as a flavoring agent in curries. Therefore, the effect of 100 mg/kg body weight curcumin was studied on the antioxidant status of mice skin exposed to a total dose of 10, 20 and 40 Gy γ-radiation below the rib cage delivered as a single fraction of 2 Gy per day for 5, 10 or 20 days. Skin biopsies from both the curcumin treated or untreated irradiated groups were collected for the biochemical estimations at various post-irradiation times. The irradiation of animals caused a dose dependent decline in the glutathione concentration, glutathione peroxidase, and superoxide dismutase activities and increased the lipid peroxidation in the irradiated skin. Curcumin treatment before irradiation resulted in a significant rise in the glutathione concentration and activities of both the glutathione peroxidase and superoxide dismutase enzymes in mouse skin, whereas lipid peroxidation declined significantly. The present study indicates that curcumin treatment increased the antioxidant status of mouse exposed to different doses of fractionated γ-radiation.

Topical application of a sandal wood oil and turmeric based cream prevents radiodermatitis in head and neck cancer patients undergoing external beam radiotherapy: a pilot study

OBJECTIVE

The study objective was to assess the effectiveness of a turmeric- and sandal wood oil-containing cream [Vicco(®) turmeric cream (VTC); Vicco Laboratories, Parel, India] on radiodermatitis in patients with head and neck cancer undergoing radiotherapy.

METHODS

A total of 50 patients with head and neck cancer requiring >60 Gy of curative radiotherapy/chemoradiotherapy were enrolled in the study. The volunteers were randomly divided into two groups of 25 patients. Group 1 was assigned to a topical application of Johnson's(®) baby oil (Johnson & Johnson Ltd, Baddi, India) and Group 2 for VTC. Prophylactic application of the cream was initiated on Day 1 and continued every day until 2 weeks after the end of treatment. Both agents were symmetrically applied within the irradiated field five times a day, and the acute skin reactions were assessed twice weekly in accordance with the Radiation Therapy Oncology Group scores by an investigator who was unaware of the details.

RESULTS

The incidence of radiodermatitis increased with the exposure to radiation and was the highest in both groups at Week 7. However, a significant reduction in grades of dermatitis were seen in cohorts applying VTC at all time points, including 2 weeks post radiotherapy (p < 0.015 to p < 0.001). The occurrence of Grade 3 dermatitis was lower in the cohorts using VTC and was statistically significant (p < 0.01). Additionally, follow-up observations 2 weeks after the completion of radiotherapy also showed a reduced degree of radiodermatitis in cohorts applying VTC, which was significant (p = 0.015).

CONCLUSION

VTC is shown to be effective in preventing radiodermatitis and needs to be validated in larger double-blind trials.

ADVANCES IN KNOWLEDGE

For the first time, this study shows that the turmeric- and sandal oil-based cream was effective in preventing radiation-induced dermatitis.