Radiation protection of DNA by ferulic acid under in vitro and in vivo conditions

Insights into the radioprotective efficacy of Pterocarpus santalinus L. aqueous extract

In the present study, we have attempted a comprehensive assessment of the possible radioprotective efficacy of Pterocarpus santalinus aqueous extract (PSAE). All the studied models were gamma-irradiated with prior treatment with PSAE. First, the content of total phenols (4.061 μg/mg gallic acid equivalents), flavonoids (6.616 μg/mg quercetin equivalents), and tannins (0.008 mg/L of PSAE) were determined spectrophotometrically. Second, UHPLC-HRMS analysis was performed to identify the possible radioprotectors. Of those, santalins A & B are known for their usage as natural color in foods and alcoholic beverages identified in PSAE. Treatment was well tolerated with no side effects from PSAE. Later, it was shown that radiation-induced lethality significantly amended in PSAE-treated spleen lymphocytes as evidenced by reduced elevated levels of ROS and lipid peroxidation, restored total thiols and GSH: GSSG, inhibited DNA DSBs and cell death. Furthermore, an immunomodulation study was carried out because radiation exposure induces an inflammatory response. Our study shows that PSAE suppressed concanavalin A-induced T-cell proliferation as evidenced by CFSE dye dilution and CD69 antibody staining methods. Taken together, the current study explored the protective efficacy of PSAE from gamma radiation-inflicted injuries and hence we recommend PSAE as a potent radioprotective formulation.

Repurposing of FDA approved kinase inhibitor bosutinib for mitigation of radiation induced damage via inhibition of JNK pathway

Radiotherapy is a common modality for cancer treatment. However, it is often associated with normal tissue toxicity in 20-80% of the patients. Radioprotectors can improve the outcome of radiotherapy by selectively protecting normal cells against radiation toxicity. In the present study, compound libraries containing 54 kinase inhibitors and 80 FDA-approved drugs were screened for radioprotection of lymphocytes using high throughput cell analysis. A second-generation FDA-approved kinase inhibitor, bosutinib, was identified as a potential radioprotector for normal cells. The radioprotective efficacy of bosutinib was evinced from a reduction in radiation induced DNA damage, caspase-3 activation, DNA fragmentation and apoptosis. Oral administration of bosutinib protected mice against whole body irradiation (WBI) induced morbidity and mortality. Bosutinib also reduced radiation induced bone-marrow aplasia and hematopoietic damage in mice exposed to 4 Gy and 6 Gy dose of WBI. Mechanistic studies revealed that the radioprotective action of bosutinib involved interaction with cellular thiols and modulation of JNK pathway. The addition of glutathione and N-acetyl cysteine significantly reduced the radioprotective efficacy of bosutinib. Moreover, bosutinib did not protect cancer cells against radiation induced toxicity. On the contrary, bosutinib per se exhibited anticancer activity against human cancer cell lines. The results highlight possible use of bosutinib as a repurposable radioprotective agent for mitigation of radiation toxicity in cancer patients undergoing radiotherapy.

Nrf2-regulated antioxidant response ameliorating ionizing radiation-induced damages explored through in vitro and molecular dynamics simulations

This study aims to investigate the mechanism of natural antioxidant ferulic acid (FA) in reducing oxidative stress followed by its inhibitory effect on the Keap1-Nrf2 complex. FA was treated ex vivo with human blood for 30 min at 37 °C ± 1 °C and exposed to 1.5 Gy of γ- rays of 60Co (0.789 Gy/min) and allowed for repair for an hour at 37 °C ± 1 °C. FA's free radical scavenging capacity was measured using 2,7-dichlorofluorescein diacetate assay and cytogenetic assays. Further, a possible mechanism of protein-ligand interaction between FA and Keap1-Nrf2 pathway protein as a cellular drug target was studied using docking and molecular dynamics simulation. The 1.5 Gy of γ- rays exposed to pre-treated blood with FA showed a significant (p < 0.05) reduction in reactive oxygen species and DNA damage compared to the normal control blood group sample. The ligand-protein transient binding interaction in molecular dynamic simulation over a period of 100 ns was consistent and stable emphasizing complementary charge between the protein and ligand, speculating higher hydrophobic amino acid residues in the Keap1 active pocket. This might sway the Keap1 from interaction with Nrf2, and could lead to nuclear translocation of Nrf2 during radiation-induced oxidative stress. The present study emphasizes the radioprotective effect of FA against 1.5 Gy of γ- rays exposed to human blood and the application of in silico approaches helpful for the possible protective effect of FA.Communicated by Ramaswamy H. Sarma.

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

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

Treatment of Human HeLa Cells with Black Raspberry Extracts Enhances the Removal of DNA Lesions by the Nucleotide Excision Repair Mechanism

As demonstrated by us earlier and by other researchers, a diet containing freeze-dried black raspberries (BRB) inhibits DNA damage and carcinogenesis in animal models. We tested the hypothesis that the inhibition of DNA damage by BRB is due, in part, to the enhancement of DNA repair capacity evaluated in the human HeLa cell extract system, an established in vitro system for the assessment of cellular DNA repair activity. The pre-treatment of intact HeLa cells with BRB extracts (BRBE) enhances the nucleotide excision repair (NER) of a bulky deoxyguanosine adduct derived from the polycyclic aromatic carcinogen benzo[a]pyrene (BP-dG) by ~24%. The NER activity of an oxidatively-derived non-bulky DNA lesion, guanidinohydantoin (Gh), is also enhanced by ~24%, while its base excision repair activity is enhanced by only ~6%. Western Blot experiments indicate that the expression of selected, NER factors is also increased by BRBE treatment by ~73% (XPA), ~55% (XPB), while its effects on XPD was modest (<14%). These results demonstrate that BRBE significantly enhances the NER yields of a bulky and a non-bulky DNA lesion, and that this effect is correlated with an enhancement of expression of the critically important NER factor XPA and the helicase XPB, but not the helicase XPD.

Phytochemicals: Potential Therapeutic Modulators of Radiation Induced Signaling Pathways

Ionizing radiation results in extensive damage to biological systems. The massive amount of ionizing radiation from nuclear accidents, radiation therapy (RT), space exploration, and the nuclear battlefield leads to damage to biological systems. Radiation injuries, such as inflammation, fibrosis, and atrophy, are characterized by genomic instability, apoptosis, necrosis, and oncogenic transformation, mediated by the activation or inhibition of specific signaling pathways. Exposure of tumors or normal cells to different doses of ionizing radiation could lead to the generation of free radical species, which can release signal mediators and lead to harmful effects. Although previous FDA-approved agents effectively mitigate radiation-associated toxicities, their use is limited due to their high cellular toxicities. Preclinical and clinical findings reveal that phytochemicals derived from plants that exhibit potent antioxidant activities efficiently target several signaling pathways. This review examined the prospective roles played by some phytochemicals in altering signal pathways associated with radiation response.

Breaking the Silence of Tumor Response: Future Prospects of Targeted Radionuclide Therapy

Therapy-induced tumor resistance has always been a paramount hurdle in the clinical triumph of cancer therapy. Resistance acquired by tumor through interventions of chemotherapeutic drugs, ionizing radiation, and immunotherapy in the patientsis a severe drawback and major cause of recurrence of tumor and failure of therapeutic responses. To counter acquired resistance in tumor cells, several strategies are practiced such as chemotherapy regimens, immunotherapy, and immunoconjugates, but the outcome is very disappointing for the patients as well as clinicians. Radionuclide therapy using alpha or beta-emitting radionuclide as payload became state-of-the-art for cancer therapy. With the improvement in dosimetric studies, development of high-affinity target molecules, and design of several novel chelating agents which provide thermodynamically stable complexes in vivo, the scope of radionuclide therapy has increased by leaps and bounds. Additionally, radionuclide therapy along with the combination of chemotherapy is gaining importance in pre-clinics, which is quite encouraging. Thus, it opens an avenue for newer cancer therapy modalities where chemotherapy, radiation therapy, and immunotherapy are unable to break the silence of tumor response. This article describes, in brief, the causes of tumor resistance and discusses the potential of radionuclide therapy to enhance tumor response.

Could Polyphenols Really Be a Good Radioprotective Strategy?

Currently, radiotherapy is one of the most effective strategies to treat cancer. However, deleterious toxicity against normal cells indicate for the need to selectively protect them. Reactive oxygen and nitrogen species reinforce ionizing radiation cytotoxicity, and compounds able to scavenge these species or enhance antioxidant enzymes (e.g., superoxide dismutase, catalase, and glutathione peroxidase) should be properly investigated. Antioxidant plant-derived compounds, such as phenols and polyphenols, could represent a valuable alternative to synthetic compounds to be used as radio-protective agents. In fact, their dose-dependent antioxidant/pro-oxidant efficacy could provide a high degree of protection to normal tissues, with little or no protection to tumor cells. The present review provides an update of the current scientific knowledge of polyphenols in pure forms or in plant extracts with good evidence concerning their possible radiomodulating action. Indeed, with few exceptions, to date, the fragmentary data available mostly derive from in vitro studies, which do not find comfort in preclinical and/or clinical studies. On the contrary, when preclinical studies are reported, especially regarding the bioactivity of a plant extract, its chemical composition is not taken into account, avoiding any standardization and compromising data reproducibility.

Pterocarpus santalinus L. extract mitigates gamma radiation-inflicted derangements in BALB/c mice by Nrf2 upregulation

Plant-based natural extracts contain several nutrients and bioactive compounds, such as phenolics and flavonoids, that possess various health-promoting activities. This study investigated the effects of polyphenols from Pterocarpus santalinus hydroalcoholic extract (PSHE) against gamma radiation-induced derangements via the upregulation of Nrf2. Ultra High Performance Liquid Chromatography Coupled to High Resolution Mass Spectrometry (UHPLC-HRMS/MS) analysis was performed to identify the possible radioprotectors. In vivo and in vitro studies, namely Real-Time-PCR (RT-PCR) analysis, Reactive Oxygen Species (ROS) scavenging activity, lipid peroxidation and GSH levels, DNA damage and cell death studies, anti-inflammatory (Sandwich ELISA), immunomodulatory studies (antibody staining), and model free radical scavenging assays, were performed. Vanillic acid, protocatechuic acid, para-hydroxybenzoic acid, chlorogenic acid, TNF-α inhibitor (Eudesmin), isoflavone (Daidzein 7-o-glucoside), astragalin (Kaempferol 3-o-glycoside), and other polyphenols were identified in PSHE using UHPLC-HRMS/MS analysis. Prophylactic administration of PSHE (-1 h) rendered more than 33% survival in mice exposed to 8 Gy whole-body-irradiation with increased mice survival and recovery of bone marrow and spleen cellularity. Real-time RT-PCR analysis showed that PSHE treatment (50 µg/mL) upregulated Nrf2, HO-1, and GPX-1 in mice splenocytes. At 50 µg/mL, PSHE reduced ROSscavenging activity, mitochondrial and spleen membrane lipid peroxidation levels, DNA damage, and cell death, and increased GSH levels. At 10 µg/mL, PSHE treatment diminished the content of IL-6 and TNF-α. At 50 µg/mL, PSHE suppressed lymphocyte proliferation. These findings indicate that polyphenols of PSHE possess marked antioxidant, anti-inflammatory, and immunomodulatory capacities, which play important roles in the prevention of radiation damage.

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.

Fluorescent polymers via post-polymerization modification of Biginelli-type polymers for cellular protection against UV damage

Biocompatible fluorescent polymers with UV-protective capability have been developed by the combination of the Biginelli reaction and the postpolymerization modification method.

Genome-Protecting Compounds as Potential Geroprotectors

Throughout life, organisms are exposed to various exogenous and endogenous factors that cause DNA damages and somatic mutations provoking genomic instability. At a young age, compensatory mechanisms of genome protection are activated to prevent phenotypic and functional changes. However, the increasing stress and age-related deterioration in the functioning of these mechanisms result in damage accumulation, overcoming the functional threshold. This leads to aging and the development of age-related diseases. There are several ways to counteract these changes: 1) prevention of DNA damage through stimulation of antioxidant and detoxification systems, as well as transition metal chelation; 2) regulation of DNA methylation, chromatin structure, non-coding RNA activity and prevention of nuclear architecture alterations; 3) improving DNA damage response and repair; 4) selective removal of damaged non-functional and senescent cells. In the article, we have reviewed data about the effects of various trace elements, vitamins, polyphenols, terpenes, and other phytochemicals, as well as a number of synthetic pharmacological substances in these ways. Most of the compounds demonstrate the geroprotective potential and increase the lifespan in model organisms. However, their genome-protecting effects are non-selective and often are conditioned by hormesis. Consequently, the development of selective drugs targeting genome protection is an advanced direction.

Nephroprotective and antioxidant effect of green tea (Camellia sinensis) against nicotine-induced nephrotoxicity in rats and characterization of its bioactive compounds by HPLC-DAD

Nicotine is a potential inducer of oxidative stress, through which it can damage numerous biological molecules. Natural antioxidants that prevent or slow the progression and severity of nicotine toxicity may have a significant health impact. The purpose of this study, conducted on Wistar rats, was to evaluate the beneficial effects of green tea (Camellia sinensis) extract on nicotine treatment-induced damage on kidney. Our results showed that nicotine significantly (p < 0.01) increased serum and kidney malondialdehyde, the serum contents of urea, creatinine, and uric acid. In addition, nicotine intoxication significantly (p < 0.01) decreased the levels of vitamins E and C in serum and kidney tissue as well as the activities of superoxide dismutase, catalase, and glutathione peroxidase. Interestingly, animals that were pretreated with green tea, prior to nicotine administration, showed a significant nephroprotection, revealed by a significant reduction-induced oxidative damage for all tested markers. The nephroprotective activity of green tea is mediated, at least in part, by the antioxidant effect of its constituents.

Protective effects ofMentha spicataagainst nicotine-induced toxicity in liver and erythrocytes of Wistar rats

The aim of this study was to investigate the protective effect of Mentha spicata supplementation against nicotine-induced oxidative damage in the liver and erythrocytes of Wistar rats. Bioactive substances were determined by liquid chromatography – electrospray ionization – tandem mass spectrometry analysis. Animals were divided into 4 groups of 6 rats each: a normal control group, a nicotine-treated group (1 mg/kg), a group receiving M. spicata extract (100 mg/kg), and a group receiving both M. spicata extract (100 mg/kg) and nicotine (1 mg/kg). Many phenolic acids were identified in the M. spicata aqueous extract. After 2 months of treatment, nicotine induced an increase in the level of white blood cells and a marked decrease in erythrocytes, hemoglobin, and haematocrit. Aspartate transaminase, alanine transaminase, alkaline phosphatase, and lactate dehydrogenase activities were also found to be higher in nicotine-treated group than those of the control group. Furthermore, nicotine-treated rats exhibited oxidative stress, as evidenced by a decrease in antioxidant enzymes activities and an increase in lipid peroxidation level in liver and erythrocytes. Interestingly, the oral administration of M. spicata extract by nicotine-treated rats alleviated such disturbances. M. spicata contained bioactive compounds that possess important antioxidant potential and protected liver and erythrocytes against nicotine-induced damage.

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.

Ferulic acid (FA) abrogates γ-radiation induced oxidative stress and DNA damage by up-regulating nuclear translocation of Nrf2 and activation of NHEJ pathway

The present study was aimed to evaluate the radioprotective effect of ferulic acid (FA), a naturally occurring plant flavonoid in terms of DNA damage and damage related alterations of repair pathways by gamma radiation. FA was administered at a dose of 50 mg/kg body weight for five consecutive days prior to exposing the swiss albino mice to a single dose of 10 Gy gamma radiation. Ionising radiation induces oxidative damage manifested by decreased expression of Cu, Zn-SOD (SOD stands for super oxide dismutase), Mn-SOD and catalase. Gamma radiation promulgated reactive oxygen species (ROS) mediated DNA damage and modified repair pathways. ROS enhanced nuclear translocation of p53, activated ATM (ataxia telangiectasia-mutated protein), increased expression of GADD45a (growth arrest and DNA-damage-inducible protein) gene and inactivated Non homologous end joining (NHEJ) repair pathway. The comet formation in irradiated mice peripheral blood mononuclear cells (PBMC) reiterated the DNA damage in IR exposed groups. FA pretreatment significantly prevented the comet formation and regulated the nuclear translocation of p53, inhibited ATM activation and expression of GADD45a gene. FA promoted the nuclear translocation of nuclear factor (erythroid-derived 2)-like 2 (Nrf2) and activated NHEJ repair pathway to overcome ROS mediated oxidative stress and DNA damage. Therefore, the current study stated that FA can challenge the oxidative stress by (i) inducing nuclear translocation of Nrf2, (ii) scavenging ROS, and (iii) activating NHEJ DNA repair process.

Protective Role of Dietary Berries in Cancer

Dietary patterns, including regular consumption of particular foods such as berries as well as bioactive compounds, may confer specific molecular and cellular protection in addition to the overall epidemiologically observed benefits of plant food consumption (lower rates of obesity and chronic disease risk), further enhancing health. Mounting evidence reports a variety of health benefits of berry fruits that are usually attributed to their non-nutritive bioactive compounds, mainly phenolic substances such as flavonoids or anthocyanins. Although it is still unclear which particular constituents are responsible for the extended health benefits, it appears that whole berry consumption generally confers some anti-oxidant and anti-inflammatory protection to humans and animals. With regards to cancer, studies have reported beneficial effects of berries or their constituents including attenuation of inflammation, inhibition of angiogenesis, protection from DNA damage, as well as effects on apoptosis or proliferation rates of malignant cells. Berries extend effects on the proliferation rates of both premalignant and malignant cells. Their effect on premalignant cells is important for their ability to cause premalignant lesions to regress both in animals and in humans. The present review focuses primarily on in vivo and human dietary studies of various berry fruits and discusses whether regular dietary intake of berries can prevent cancer initiation and delay progression in humans or ameliorate patients’ cancer status.

Protection against Radiotherapy-Induced Toxicity

Radiation therapy is a highly utilized therapy in the treatment of malignancies with up to 60% of cancer patients receiving radiation therapy as a part of their treatment regimen. Radiation therapy does, however, cause a wide range of adverse effects that can be severe and cause permanent damage to the patient. In an attempt to minimize these effects, a small number of compounds have been identified and are in use clinically for the prevention and treatment of radiation associated toxicities. Furthermore, there are a number of emerging therapies being developed for use as agents that protect against radiation-induced toxicities. The aim of this review was to evaluate and summarise the evidence that exists for both the known radioprotectant agents and the agents that show promise as future radioprotectant agents.

The protective role of ferulic acid on sepsis-induced oxidative damage in Wistar albino rats

Oxidative stress has an important role in the development of sepsis-induced multiorgan failure. Ferulic acid (FA), a well-established natural antioxidant, has several pharmacological activities including anti-inflammatory, anticancer and hepatoprotective. This study aimed to investigate the effects of FA on sepsis-induced oxidative damage in Wistar albino rats. Sepsis-induced DNA damage in the lymphocytes, liver and kidney cells of rats were evaluated by comet assay with and without formamidopyrimidine DNA glycosylase (Fpg). The oxidative stress parameters such as superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities and total glutathione (GSH) and malondialdehyde (MDA) levels were also measured. It is found that DNA damage in sepsis+FA-treated group was significantly lower than the sepsis group. FA treatment also decreased the MDA levels and increased the GSH levels and SOD and GSH-Px activities in the sepsis-induced rats. It seems that FA might have ameliorative effects against sepsis-induced oxidative damage.

Effects of sodium ferulate on preventing steroid-induced femoral head osteonecrosis in rabbits

The aim of this study is to investigate the effects and possible mechanisms of sodium ferulate (SF) on anti-apoptosis in steroid-induced femoral head osteonecrosis in rabbits. Japanese white rabbits were randomly divided into three groups (control group, treatment group, and model group), each with 24 rabbits. The model and treatment groups were first injected with an intravenous dose of horse serum, 10 ml/kg, three weeks later with an intravenous dose of 7.5 ml/kg, and two weeks later with an intramuscular dose of methylprednisolone, 45 mg/kg, three times in order to establish rabbit models of osteonecrosis. Concurrently, the treatment group was injected with intravenous doses of SF 20 mg/kg for two weeks, once per day. Three time points, Weeks 2, 4, and 8, were selected after modeling was completed. Osteonecrosis was verified by histopathology with haematoxylin-eosin (HE) staining. The apoptosis rate of osteonecrosis was observed by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. The apoptosis expressions of caspase-3 and Bcl-2 were analyzed by immunohistochemistry and Western blot. The rabbit models of osteonecrosis were successfully established and observed by HE staining. SF was effective in intervening in apoptosis and decreasing the apoptosis rate in femoral head necrosis by the immunohistochemistry and TUNEL assay (P<0.01). Western blot analysis indicated that there were statistical significances in the protein levels of caspase-3 and Bcl-2 (P<0.01). SF has a protective effect by reducing the incidence of early steroid-induced femoral head necrosis in rabbits, effectively intervening in apoptosis through decreasing caspase-3 expression and up-regulating Bcl-2 expression.

Ferulic acid and derivatives: molecules with potential application in the pharmaceutical field

Ferulic acid is a phenolic acid widely distributed in the plant kingdom. It presents a wide range of potential therapeutic effects useful in the treatments of cancer, diabetes, lung and cardiovascular diseases, as well as hepatic, neuro and photoprotective effects and antimicrobial and anti-inflammatory activities. Overall, the pharmaceutical potential of ferulic acid can be attributed to its ability to scavenge free radicals. However, recent studies have revealed that ferulic acid presents pharmacological properties beyond those related to its antioxidant activity, such as the ability to competitively inhibit HMG-CoA reductase and activate glucokinase, contributing to reduce hypercholesterolemia and hyperglycemia, respectively. The present review addresses ferulic acid dietary sources, the pharmacokinetic profile, antioxidant action mechanisms and therapeutic effects in the treatment and prevention of various diseases, in order to provide a basis for understanding its mechanisms of action as well as its pharmaceutical potential.

Determination of ferulic acid by flow injection chemiluminescence analysis based on enhancement of the N-bromobutanimide-eosin-CrCl3 system in alkaline solution

A simple and sensitive flow injection chemiluminescence method has been developed for the determination of ferulic acid (FA) based on the significant enhancement effect of FA on the CL signal of the N-bromobutanimide (NBS)-eosin-CrCl3 system in alkaline solution. Under optimum conditions, the enhanced CL intensity is linearly related to the concentration of FA in its pharmaceutical preparations and human plasma samples. The corresponding linear regression equations were established over the 4.0 × 10(-10)-1.0 × 10(-7) g/mL for FA tablets and 2.0 × 10(-10)-1.0 × 10(-7) g/mL for plasma samples. The limit of detection for FA tablets and limit of quantification for plasma samples were 2.8 × 10(-10) g/mL (3 σ) and 3.04 × 10(-10) g/mL (10 σ), respectively. A complete analysis could be performed within 40 s, including washing and sampling, giving a throughput of ≈90/h. The proposed method was successfully applied to the determination of FA in pharmaceutical preparations and human plasma samples with satisfactory results. The recoveries of pharmaceutical preparations and human plasma samples at three different concentrations were 97.8-102.6% and 96.7-104.0%, respectively. Furthermore, the possible mechanism of CL reactions was also discussed briefly.

A novel microplate-based assay for screening radioprotectors and its validation based on DNA and membrane system

Ionizing radiation leads to damage at various cellular and sub-cellular levels and can be prevented by radioprotectors. There are many in vitro and in vivo but rather expensive assays for screening of radioprotectors from natural and synthetic sources. We have developed a cell free radioprotector screening assay which involves bleaching of crocin pigment, isolated from saffron by radiolytic products of water. Any molecules/compounds which can inhibit the bleaching of the crocin will act as a radioprotector. The developed assay was further validated by the existing in vitro assays. Different radioprotectors have different level for inhibition of bleaching of crocin. The trends of radioprotection offered by crocin bleaching assay, plasmid relaxation and lipid peroxidation are TMG>FA>VA>Amifos>Trox, TMG>VA>FA>Amifos>Trox, and TMG>FA>Trox>VA>Amifos, respectively. We are getting different trends for different assays. This is because different drugs have different mechanisms of radioprotection in different assay systems. In conclusion, the crocin bleaching assay developed here is a simple, fast and economical screening assay and it will have great value in radioprotection programme for screening many potential compounds for radioprotection.

Ferulic acid, a dietary phenolic acid, modulates radiation effects in Swiss albino mice

The radioprotective efficacy of Ferulic acid (FA) against whole body gamma radiation was studied in Swiss albino mice. To study the radiation protection, mice were administered with ferulic acid intraperitoneally (i.p) (50 mg/kg body weight.), once daily for five consecutive days. One hour after the last administration of ferulic acid on the sixth day, animals were whole body exposed to 8 Gy gamma radiations. Effect of ferulic acid pretreatment on radiation-induced changes in antioxidant enzymes and lipid peroxidation status in spleen, liver and intestine was analyzed. A significant increase in the antioxidant enzymatic status and decreased lipid peroxidation marker levels were observed in ferulic acid pretreated group, when compared to the irradiated animals. Our study also shows increased % tail DNA, tail length, tail moment and Olive tail moment in irradiated mice blood lymphocytes. Ferulic acid (50 mg/kg body weight) pretreatment significantly decreased the % tail DNA, tail length, tail moment and Olive tail moment in irradiated mice lymphocytes. The histological observations indicated a decline in the villus height and crypt number with an increase in goblet and dead cell population in the irradiated group, which was normalized by ferulic acid pretreatment. In conclusion, present study indicated ferulic acid treatment prevents radiation-induced lipid peroxidation, DNA damage and restored antioxidant status and histopathological changes in experimental animals.

Protective effect of vitamin E and epicatechin against nicotine-induced oxidative stress in rats

Nicotine is a major pharmacologically active and addictive component of tobacco smoke, which is regarded to be a primary risk factor in the development of cardiovascular and pulmonary diseases. Epicatechin is one of the most potent antioxidants present in the human diet. Particularly high levels of this compound are found in tea, apples and chocolate. It has been reported that tea extracts and/or its constituents have antibacterial, antiviral, antioxidative, antitumor and antimutagenic activities. Vitamin E is a major lipid-soluble antioxidant vitamin and free radical scavenger, presents as an integral component of cellular membranes and has important biological functions. The primary mechanism by which vitamin E is proposed to prevent cancer is through their antioxidant properties. The goal of this study is to evaluate the effect of epicatechin alone or combined with vitamin E in inhibiting the oxidative stress induced by nicotine in rats. Results obtained indicated that there was a significant elevation in the levels of malondialdhyde (MDA) in nicotine injected rats. The combined treatment (epicatechin + Vit E) group showed a potential reduction of these parameters more than individual treatment. The activities of superoxide dismutase, catalase and glutathione peroxidase were found significantly higher in combined treated than untreated rats. In nicotine group, a negative significant correlation between reduced glutathione and MDA (r = -0.92) was observed. In conclusion, these results suggested that the supplementation of diet with epicatechin and vitamin E provided antioxidant defense with strong chemopreventive activity against nicotine-induced carcinogenesis.

Ferulic acid-induced anti-depression and prokinetics similar to Chaihu-Shugan-San via polypharmacology

Selective serotonin reuptake inhibitors (SSRIs), one of popular antidepressants as "one-compound-one-target" paradigm, cannot but discontinue because of inhibiting gut movement. Traditional Chinese medicine (TCM) Chaihu-Sugan-San (CSS) can simultaneously exert anti-depression and prokinetics. From this thread, we aimed to find a new antidepressant with polypharmacological mechanisms. In vivo antidepressive and prokinetic comparisons between CSS and its absorbed compound ferulic acid (FA) were made. And FA's action mechanisms involved in monoaminergic systems, HPA axis and gastrointestinal peptide ghrelin was then studied in forced swimming test (FST) of rat. Lastly, the jejunal contraction activity evoked by FA was measured in vitro. Compared with vehicle, FA reduced immobility time, increased locomotor activity, accelerated gastric emptying and intestinal transit similar to CSS whose absorbable component FA was identified in hippocampus and jejunum. FA's prokinetics in vivo was further supported by its jejunal contraction in vitro. FA-induced anti-immobility was prevented by pretreated with PCPA, WAY-100635, ketanserin, sulpiride, SCH233390, haloperidol and yohimbine, respectively. CRH, ACTH and 5-HT were significantly decreased, but ghrelin was apparently increased compared with vehicle. In summary, FA induced anti-depression and prokinetics similar to CSS via inhibiting serotonin, norepinephrine and dopamine reuptakes, regulating HPA axis, increasing ghrelin and stimulating jejunal contraction simultaneously.

Ferulic acid protects against carbon tetrachloride-induced liver injury in mice

Ferulic acid (FA), isolated from the root of Scrophularia buergeriana, is a phenolic compound possessing antioxidant, anticancer, and antiinflammatory activities. Here, we have investigated the hepatoprotective effect of FA against carbon tetrachloride (CCl(4))-induced acute liver injury. Mice were treated intraperitoneally with vehicle or FA (20, 40, and 80mg/kg) 1h before and 2h after CCl(4) (20μl/kg) injection. The serum activities of aminotransferases and the hepatic level of malondialdehyde were significantly higher after CCl(4) treatment, while the concentration of reduced glutathione was lower. These changes were attenuated by FA. The serum level and mRNA expression of tumor necrosis factor-α significantly increased after CCl(4) treatment, and FA attenuated these increases. The levels of inducible nitric oxide synthase and cyclooxygenase-2 protein and mRNA expression after CCl(4) treatment were significantly higher and FA reduced these increases. CCl(4)-treated mice showed increased nuclear translocation of nuclear factor-κB (NF-κB), and decreased levels of inhibitors of NF-κB in cytosol. Also, CCl(4) significantly increased the level of phosphorylated JNK and p38 mitogen-activated protein (MAP) kinase, and nuclear translocation of activated c-Jun. FA significantly attenuated these changes. We also found that acute CCl(4) challenge induced TLR4, TLR2, and TLR9 protein and mRNA expression, and FA significantly inhibited TLR4 expression. These results suggest that FA protects from CCl(4)-induced acute liver injury through reduction of oxidative damage and inflammatory signaling pathways.

Effects of ferulic acid on hematopoietic cell recovery in whole-body gamma irradiated mice

PURPOSE

The objective of this study was to investigate the mechanism for ferulic acid (FA)-induced radioprotection by evaluating the recovery of bone marrow cells and peripheral blood hematology.

MATERIALS AND METHODS

Balb/c mice were irradiated at a dose of 2.5 Gy using cobalt-60 gamma resources. Following irradiation, FA was administered intragastrically for seven consecutive days. Hematopoietic progenitor colony-forming cell assays were used to assess the reconstitution of bone marrow after radiation-induced myelosuppression. Cytokine levels were investigated using enzyme-linked immunosorbent assay and Western blot analysis.

RESULTS

The results demonstrated that FA treatment enhanced hematopoietic progenitor cell activity resulting in accelerated blood cell recovery. FA administration increased levels of granulocyte-colony stimulating factor (G-CSF) and erythropoietin.

CONCLUSION

These results suggest radioprotective efficacy by FA may be a result of early recovery of hematopoietic cells due to enhanced production of G-CSF and erythropoietin.

In vivo protective effect of ferulic acid against noise-induced hearing loss in the guinea-pig

Ferulic acid (FA) is a phenolic compound whose neuroprotective activity was extensively studied in vitro. In this study, we provided functional in vivo evidence that FA limits noise-induced hearing loss. Guinea-pigs exposed to acoustic trauma for 1 h exhibited a significant impairment in auditory function; this injury was evident as early as 1 day from noise exposure and persisted over 21 days. Ferulic acid (150 mg/kg i.p. for 4 days) counteracted noise-induced hearing loss at days 1, 3, 7 and 21 from noise exposure. The improvement of auditory function by FA was paralleled by a significant reduction in oxidative stress, apoptosis and increase in hair cell viability in the organ of Corti. Interestingly in the guinea-pig cochleae, the neuroprotective effect of FA was functionally related not only to its scavenging ability in the peri-traumatic period but also to the up-regulation of the cytoprotective enzyme heme oxygenase-1 (HO-1); in fact, FA-induced improvement of auditory function was counteracted by the HO inhibitor zinc-protoporphyrin-IX and paralleled the time-course of HO-1 induction over 3-7 days. These results confirm the antioxidant properties of FA as free-radical scavenger and suggest a role of HO-1 as an additional mediator against noise-induced ototoxicity.

Ferulic acid protects human umbilical vein endothelial cells from radiation induced oxidative stress by phosphatidylinositol 3-kinase and extracellular signal-regulated kinase pathways

Ferulic acid (FA) has been demonstrated to have a remarkable antioxidant activity, the mechanism of FA of protecting human umbilical vein endothelial cells (HUVECs) from radiation induced oxidative stress was investigated in the present study. The oxidative protection of FA was assessed by cellular glutathione (GSH) content, nicotinamide adenine dinucleotide phosphate (NADPH) levels, and reactive oxygen species (ROS) analysis. Nuclear factor erythroid 2-related factor 2 (Nrf2) nuclear translocation was detected using Western blotting. The upstream signaling pathway involved in FA mediated Nrf2 activation was determined by signaling inhibitors. FA significantly increased the transcription of antioxidant related genes such as GCLC (glutamate-cysteine ligase catalytic subunit), GCLM (glutamate-cysteine ligase regulatory subunit), NQO1 (NADPH quinone oxidoreductase-1) and heme oxygenase-1 (HO-1) mRNA in radiated cells, and these changes involved in a significant increase of the intracellular GSH content and the expression of NAPDH. FA evidently promoted Nrf2 translocation into nuclei and increased the intracellular GSH and NADPH levels in radiated cells. Phosphatidylinositol 3-kinase (PI3K) and extracellular signal regulated kinase (ERK) pathways were associated with FA-induced Nrf2 activation. The results suggested that FA-induced Nrf2 activation play key role in cytoprotective effect of FA against oxidative stress via PI3K and ERK signaling pathways.

The protective effect of epicatchin against oxidative stress and nephrotoxicity in rats induced by cyclosporine

Cyclosporine A (CyA) is the first-line immunosuppressant used for the management of solid organ transplantation and autoimmune diseases. Reactive oxygen species (ROS) can attack all types of macromolecules including DNA and damage it. Epicatechin (EC) is one of the most potent antioxidants present in the human diet. Particularly high levels of this compound are found in tea, apples, and chocolate. The goal of this study was to evaluate the protective effect of EC against CyA toxicity and its antioxidant activity in transplanted patients to avoid its side effects. Results obtained showed that, CyA exert its toxic effect by increasing the free radicals and ROS that causes lipid peroxidation and cell damage, this is detected by elevation of hydroperoxides and thiobarbituric acid reactive substances, while the activities of antioxidant enzymes include (superoxide dismutase [SOD], catalase [CAT] and glutathione peroxidase [GPx]) were significantly decreased as compared with control rats. The deleterious toxic effects of CyA are, at least in part, due to increased production of free radicals and ROS. Treatment of rats with epicatchin ameliorates the toxicity of CyA by decreasing the lipid peroxidation and enhanced the antioxidants enzyme activities.