Investigation of the radioprotective efficacy of hesperidin against gamma-radiation induced cellular damage in cultured human peripheral blood lymphocytes

Mitigation effect of hesperidin on X-ray radiation-induced intestinal barrier dysfunction in Caco-2 cell monolayers

The tight junctions (TJs) and barrier function of the intestinal epithelium are highly sensitive to radiation. However, polyphenols can be used to reverse the effects of radiation. Here, we investigated the effects of hesperidin (hesperetin-7-rhamnoglucoside) on X-ray-induced intestinal barrier dysfunction in human epithelial Caco-2 monolayers. To examine whether hesperidin mitigated the effects of X-ray exposure (2 Gy), cell survival was evaluated and intestinal barrier function was assessed by measuring the transepithelial flux, apparent permeability coefficient (Papp), and barrier integrity. Hesperidin improved the survival of Caco-2 cell monolayers and attenuated X-ray exposure-induced intestinal barrier dysfunction. For fluorescein transport experiments, transepithelial flux and Papp of fluorescein in control group were significantly elevated by X-ray, but were restored to near control by 10 μM hesperidin pretreatment. Further, X-ray exposure decreased the barrier integrity and TJ interruption by reducing TJ-related proteins occludin and claudin-4, whereas cell monolayers pretreated with hesperidin before X-ray exposure were reinstated to control level. It was concluded that hesperidin treatment before X-ray exposure alleviated X-ray-induced intestinal barrier dysfunction through regulation of TJ-related proteins. These results indicate that hesperidin prevents and mitigates X-ray-induced intestinal barrier dysfunction.

Comparison of the radioprotective effects of the liposomal forms of five natural radioprotectants in alleviating the adverse effects of ionising irradiation on human lymphocytes and skin cells in radiotherapy

This study aims to evaluate the radioprotective effects of liposomes encapsulating curcumin (Lip-CUR), silibinin (Lip-SIL), α-tocopherol (Lip-TOC), quercetin (Lip-QUE) and resveratrol (Lip-RES) in alleviating the adverse effects of ionising irradiation on human lymphoctyes and skin cells in radiotherapy. Liposomes encapsulating the above natural radioprotectants (Lip-NRPs) were prepared by the film hydration method combined with sonication. Their radioprotective effects for the cells against X-irradiation was evaluated using trypan-blue assay and γ-H2AX assay. All prepared Lip-NRPs had a mean diameter less than 240 nm, polydispersity index less than 0.32, and zeta potential more than -23 mV. Among them, the radioprotective effect of Lip-RES was lowest, while that of Lip-QUE was highest. Lip-SIL also exhibited a high radioprotective effect despite its low DPPH-radical scavenging activity (12.9%). The radioprotective effects of Lip-NRPs do not solely depend on the free radical scavenging activity of NRPs but also on their ability to activate cellular mechanisms.

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.

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.

Phytochemicals: A potential next generation agent for radioprotection

BACKGROUND

Radiation hazards are accountable for extensive damage in the biological system and acts as a public health burden. Owing to the rapid increasing in radiation technology, both Ionizing radiation (IR) from natural and man made source poses detrimental outcome to public health. IR releases free radicals which induces oxidative stress and deleterious biological damage by modulating radiation induced signalling intermediates. The efficacy of existing therapeutic approach and treatment strategy are limited owing to their toxicity and associated side effects. Indian system of traditional medicine is enriched with prospective phytochemicals with potential radioprotection ability.

PURPOSE

The present review elucidated and summarized the potential role of plant derived novel chemical compound with prospective radioprotective potential.

METHOD

So far as the traditional system of Indian medicine is concerned, plant kingdom is enriched with potential bioactive molecules with diverse pharmacological activities. We reviewed several compounds mostly secondary metabolites from plant origin using various search engines.

RESULTS

Both compounds from land plants and marine source exhibited antioxidant antiinflammatory, free radical scavenging ability. These compounds have tremendous potential in fine-tuning of several signalling intermediates, which are actively participated in the progression and development of a pathological condition associated with radiation stress.

CONCLUSION

Development and explore of an operational radioprotective agent from originated from plant source that can be used as a novel molecular tool to eliminate the widespread damage caused by space exploration, ionizing radiation, nuclear war and radiotherapy has been significantly appreciated. Through extensive literature search we highlighted several compounds from both land plant and marine origin can be implemented for a better therapeutic potential against radiation induced injury. Furthermore, extensive clinical trials must be carried out in near future for better therapeutic modality and clinical efficacy.

Hepatotoxicity and renal toxicity induced by radiation and the protective effect of quercetin in male albino rats

PURPOSE

Although radiation is one of the basic methods commonly used in cancer treatment, it inevitably enters the field of treatment in healthy tissues and is adversely affected by the acute and chronic side effects of radiation. This study evaluated the possible protective effects of quercetin, an antioxidant agent, against liver and kidney damage in rats exposed to a whole-body single dose of radiation (10 Gy of gamma-ray).

MATERIALS AND METHODS

The study groups were formed as control, sham, quercetin, radiation, quercetin + radiation and radiation + quercetin using 60 male Wistar albino (200-250 g, 3 months old) rats, including 10 rats in each group. The gamma-ray provided by the Co60 teletherapy machine was given to the whole body as external irradiation. According to the groups, quercetin was administered to rats at 50 mg/kg/day via oral gavage before or after radiation administration. The rats were sacrificed the day after irradiation and the extracted tissue samples from all groups were compared histologically and immunohistochemically. DNA damage was determined by the neutral comet assay technique. Also, malondialdehyde (MDA) and glutathione peroxidase (GSH) were evaluated in liver and kidney tissues by the ELISA method.

RESULTS

Histopathological changes were observed altered morphology of liver and kidney tissues in the radiation groups. Sinusoidal dilatations, vacuolization, and hepatic parenchyma necrosis in the liver, while in kidneys, glomerular shrinkage, widened Bowman's space, tubular dilatation, and inflammation were evident. TNF-α, IL1-α, HIF1-α, and caspase 3 immunoreactivities in tissues were determined by immunohistochemistry. High caspase 3 positive cell number confirmed apoptosis, the comet parameters were decreased in the quercetin + radiation group. When compared to the control group, the exposure to radiation showed a marked elevation in MDA which was accompanied by high GSH. This damage was reduced in the quercetin + radiation group.

CONCLUSIONS

With the results obtained from the study; Quercetin is thought to have a protective potential against radiation-induced liver and kidney damage due to its radioprotective effect.

Hesperidin Modulates Troponin-1 Serum Level and Decrease Heart Tissue Injury of Irradiated Rats

BACKGROUND

The heart is the major dose-limiting organ for radiotherapy of malignant tumor in the mediastanal region.

OBJECTIVE

This study aims to investigate the radio protective effects of Hesperidin (HES) as a natural flavonoid after localized irradiation of the rat's mediastinum region.

MATERIAL AND METHODS

In this experimental study, we divided sixty male rats into 4 groups (n=15). First group: Sham which received PBS; second group: Hesperidin only (100 mg/kg/day orally) for one week; third group: Radiation that received single dose of 20 Gy gamma radiation using Co-60 unit and the forth group: Radiation+HES that underwent the same dose of radiation and received HES for 7 days prior irradiation. Each group was divided in two branches. Early sampling from subgroup one was done 4-6 hours after irradiation to determine troponin-1 level changes. Rats of second subgroups were killed 56 days after irradiation for histopathological evidence.

RESULTS

In radiation group, troponin -1 serum level had a significant increase in comparison with sham group (P<0.05). Histopathological evaluation of second subgroup showed there was a significant difference between sham and radiation group in some parameters. Inflammation (p=0.008), pericardial effusion (P=0.001), and vascular plaque (P=0.001) had an increase in the irradiation group. Oral administration of hesperidin significantly decreased all the above factors when was compared with irradiation group (P>0.016).

CONCLUSION

Oral administration of Hesperidine for seven days prior radiotherapy may decrease troponin-1 and cardiac injury due to radiation.

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.

Protective effects of dried mature Citrus unshiu peel (Chenpi) and hesperidin on aspirin-induced oxidative damage

Here we investigated the inhibitory effects in rats of mature Citrus unshiu peel (Chenpi) and its component hesperidin on aspirin-induced oxidative damage. The content of hesperidin in Chenpi extract was approximately 11.4%. Wistar rats were orally administered Chenpi extract or hesperidin (20 mg/kg body weight) and then were orally administered aspirin (200 mg/kg body weight) to induce oxidative damage to the stomach, liver, and kidneys. Such damage was evaluated using the formamidopyrimidine DNA glycosylase-modified comet assay. We also measured the amount of the oxidative marker 8-oxo-7,8-dihydroguanine (8-oxodG) in the stomach. Aspirin-induced damage to the gastric mucosa was evaluated using a bleeding score. Chenpi extract and hesperidin significantly inhibited aspirin-induced oxidative DNA damage. The bleeding score of the aspirin-induced gastric mucosa was significantly reduced by treatment with Chenpi extract and hesperidin. To investigate the effects of Chenpi extract and hesperidin on the analgesic effect of aspirin on ddY mice, we employed the acetic acid-induced writhing response test. Chenpi extract and hesperidin did not significantly affect the analgesic effect of aspirin. These results suggest that Chenpi extract and hesperidin significantly inhibit aspirin-induced gastric mucosal damage.

Histopathologic Evaluation of Radio-Protective Effect of Hesperidin on the Liver of Sprague Dawely Rats

BACKGROUND

Hesperidin is a bioflavonoid glycoside mainly found in citrus fruit and has been shown radio-protective potential in various measurement systems.

OBJECTIVE

In this article aims to investigate the radio-protective effect of hesperidin on the liver of Sprague Dawely rats.

MATERIAL AND METHODS

In this clinical study, 40 male rats were selected randomly and divided into 8 groups. Group 1 did not receive radiation and hesperidin (sham control). Group 2 received only 100 mg/kg body weight (b.w) of hesperidin for 7 consecutive days (HES group); group 3 exposed to dose of 2Gy whole body gamma radiation (2Gy group), and group 4 and 5 received 50 and 100 mg/kg b.w of HES for 7 consecutive days before 2 Gy gamma radiation, respectively.Group 6 exposed to dose of 8Gy gamma radiation (8Gy group); group 7 and 8 received 50 and 100 mg/kg b.w of HES for 7 days before 8Gy gamma irradiation, respectively. Histopathological evaluation was perfomred 24 hours after radiation.

RESULTS

Administration of hesperidin (50 mg/kg b.w, 7 days) before 2Gy of gamma irradiation led to remove inflammatory mononuclear cells in the portal space. Microscopic findings in the groups receiving two doses of hesperidin (50 and 100 mg/kg b.w, orally, 7 days), before 8Gy of gamma radiation, were similar in a way that extreme dilation of central veins to be seen, however, there was no capillarization.

CONCLUSION

HES can be offered as a suitable radio-protector in radiotherapy patients and radiation workers.

Radioprotective Effect of Hesperidin: A Systematic Review

Background and objectives: Ionizing radiation (IR) has been of immense benefit to man, especially for medical purposes (diagnostic imaging and radiotherapy). However, the risks of toxicity in healthy normal cells, leading to cellular damage as well as early and late side effects, have been major drawbacks. The aim of this study was to evaluate the radioprotective effect of hesperidin against IR-induced damage. Materials and Methods: The preferred reporting items for systematic reviews and meta-analyses (PRISMA) were applied in reporting this study. A search was conducted using the electronic databases PubMed, Scopus, Embase, Google Scholar, and www.ClinicalTrials.gov for information about completed or ongoing clinical trials. Results: From our search results, 24 studies involving rats, mice, and cultured human and animal cells were included. An experimental case-control design was used in all studies. The studies showed that the administration of hesperidin reduced oxidative stress and inflammation in all investigated tissues. Furthermore, it increased 30-day and 60-day survival rates and protected against DNA damage. The best radioprotection was obtained when hesperidin was administered before irradiation. Conclusions: The results of the included studies support the antioxidant, anti-inflammatory, and antiapoptotic abilities of hesperidin as a potential radioprotective agent against IR-induced damage. We recommend future clinical trials for more insights.

Aloe vera modulates X-ray induced hematological and splenic tissue damage in mice

The present study was premeditated to examine the radioprotective effects of aqueous Aloe vera gel extract against whole-body X-ray irradiation-induced hematological alterations and splenic tissue injury in mice. Healthy male balb/c mice were divided into four groups: group 1, control; group 2, A. vera (50 mg/kg body weight) administered per oral on alternate days for 30 days (15 times); group 3, X-ray exposure of 2 Gy (0.25 Gy twice a day for four consecutive days in the last week of the experimental protocol); and group 4, A. vera + X-ray. X-ray exposure caused alterations in histoarchitecture of spleen along with enhanced clastogenic damage as assessed by micronucleus formation and apoptotic index. Irradiation caused an elevation in proinflammatory cytokines like tumor necrosis factor and interleukin-6, total leucocyte counts, neutrophil counts and decreased platelet counts along with unaltered red blood cell counts and hemoglobin. Irradiation also caused an elevation in reactive oxygen species (ROS), lipid peroxidation (LPO) levels, lactate dehydrogenase activity and alterations in enzymatic and nonenzymatic antioxidant defense mechanism in plasma and spleen. However, administration of A. vera gel extract ameliorated X-ray irradiation-induced elevation in ROS/LPO levels, histopathological and clastogenic damage. It also modulated biochemical indices, inflammatory markers, and hematological parameters. These results collectively indicated that the A. vera gel extract offers protection against whole-body X-ray exposure by virtue of its antioxidant, anti-inflammatory and anti-apoptotic potential.

Multivitamin and Mineral Supplementation Containing Phytonutrients Scavenges Reactive Oxygen Species in Healthy Subjects: A Randomized, Double-Blinded, Placebo-Controlled Trial

Phytonutrients and vitamin and mineral supplementation have been reported to provide increased antioxidant capacity in humans; however, there is still controversy. In the current clinical trial, we examined the antioxidant and DNA protection capacity of a plant-based, multi-vitamin/mineral, and phytonutrient (PMP) supplementation in healthy adults who were habitually low in the consumption of fruits and vegetables. This study was an eight-week, double-blind, randomized, parallel-arm, and placebo-controlled trial. PMP supplementation for eight weeks reduced reactive oxygen species (ROS) and prevented DNA damage without altering endogenous antioxidant system. Plasma vitamins and phytonutrients were significantly correlated with ROS scavenging and DNA damage. In addition, gene expression analysis in PBMC showed subtle changes in superoxide metabolic processes. In this study, we showed that supplementation with a PMP significantly improved ROS scavenging activity and prevented DNA damage. However, additional research is still needed to further identify mechanisms of actions and the role of circulating phytonutrient metabolites.

Early Response Monitoring Following Radiation Therapy by Using [18F]FDG and [11C]Acetate PET in Prostate Cancer Xenograft Model with Metabolomics Corroboration

We aim to characterize the metabolic changes associated with early response to radiation therapy in a prostate cancer mouse model by 2-deoxy-2-[¹⁸F]fluoro-d-glucose ([¹⁸F]FDG) and [¹¹C]acetate ([¹¹C]ACT) positron emission tomography, with nuclear magnetic resonance (NMR) metabolomics corroboration. [¹⁸F]FDG and [¹¹C]ACT PET were performed before and following irradiation (RT, 15Gy) for transgenic adenocarcinoma of mouse prostate xenografts. The underlying metabolomics alterations of tumor tissues were analyzed by using ex vivo NMR. The [¹⁸F]FDG total lesion glucose (TLG) of the tumor significant increased in the RT group at Days 1 and 3 post-irradiation, compared with the non-RT group (p < 0.05). The [¹¹C]ACT maximum standard uptake value (SUVmax) in RT (0.83 ± 0.02) and non-RT groups (0.85 ± 0.07) were not significantly different (p > 0.05). The ex vivo NMR analysis showed a 1.70-fold increase in glucose and a 1.2-fold increase in acetate in the RT group at Day 3 post-irradiation (p < 0.05). Concordantly, the expressions of cytoplasmic acetyl-CoA synthetase in the irradiated tumors was overexpressed at Day 3 post-irradiation (p < 0.05). Therefore, TLG of [¹⁸F]FDG in vivo PET images can map early treatment response following irradiation and be a promising prognostic indicator in a longitudinal preclinical study. The underlying metabolic alterations was not reflected by the [¹¹C]ACT PET.

Combinations of genotoxic tests for the evaluation of group 1 IARC carcinogens

Many of the known human carcinogens are potent genotoxins that are efficiently detected as carcinogens in human populations but certain types of compounds such as immunosuppressants, sex hormones, etc. act via non-genotoxic mechanism. The absence of genotoxicity and the diversity of modes of action of non-genotoxic carcinogens make predicting their carcinogenic potential extremely challenging. There is evidence that combinations of different short-term tests provide a better and efficient prediction of human genotoxic and non-genotoxic carcinogens. The purpose of this study is to summarize the in vivo and in vitro comet assay (CMT) results of group 1 carcinogens selected from the International Agency for Research on Cancer and to discuss the utility of the comet assay along with other genotoxic assays such as Ames, in vivo micronucleus (MN), and in vivo chromosomal aberration (CA) test. Of the 62 agents for which valid genotoxic data were available, 38 of 61 (62.3%) were Ames test positive, 42 of 60 (70%) were in vivo MN test positive and 36 of 45 (80%) were positive for the in vivo CA test. Higher sensitivity was seen in in vivo CMT (90%) and in vitro CMT (86.9%) assay. Combination of two tests has greater sensitivity than individual tests: in vivo MN + in vivo CA (88.6%); in vivo MN + in vivo CMT (92.5%); and in vivo MN + in vitro CMT (95.6%). Combinations of in vivo or in vitro CMT with other tests provided better sensitivity. In vivo CMT in combination with in vivo CA provided the highest sensitivity (96.7%).

The Radioprotective Effect of Resveratrol Against Genotoxicity Induced by γ-Irradiation in Mice Blood Lymphocytes

In this study, we evaluated whether the protective potential of resveratrol (RSV; 3,5,4'-trihydroxy-trans-stilbene) against γ-radiation caused damages in peripheral blood lymphocyte of mice. Resveratrol as a polyphenolic compound scavenges free radicals. Various doses of RSV were administered intraperitoneally 2 hours to adult male mice before a single dose of whole-body γ-irradiation (2 Gy). To assess the protective ability of RSV, the alkaline comet assay in blood lymphocyte of mice was performed and the total comet score was evaluated. The results of the alkaline comet assay showed that RSV significantly inhibited radiation-induced DNA damage. We observed that RSV protects blood lymphocyte against radiation-induced damage in mice.

Radio-protective effect and mechanism of 4-Acetamido-2,2,6,6- tetramethylpiperidin-1-oxyl in HUVEC cells

OBJECTIVES

To search for more effective radiation protectors with minimal toxicity, a water-soluble nitroxides Acetamido-Tempol (AA-Tempol) was evaluated for potential radioprotective properties in HUVEC cells (Human Umbilical Vein Endothelial cell line).

METHODS

To study the anti-radiation effect of AA-Tempol in cell culture, the viability of irradiated HUVEC cells using a clonogenic survival assay was examined. The anti-apoptosis effects of AA-Tempol using Annexin V/propidium iodide staining in a flow cytometry assay was also evaluated. To elucidate the molecular mechanism of the anti-apoptosis effect of AA-Tempol against X-radiation induced HUVEC cell apoptosis, the expression of Bax, Bcl-2 and p53 and caspase-3 were examined. The changes in the level of malondialdehyde (MDA) and glutathione (GSH) in HUVEC cells after X-radiation were also investigated.

RESULTS

Pretreatment of the HUVEC cells colony with AA-Tempol 1 h before X-radiation significantly increased the colony survival (p < 0.05) compared with the cells without pretreatment. This demonstrates that AA-Tempol provides an effective radiation protection in the irradiated HUVEC cells, thus reducing apoptosis from 20.1 ± 1.3% in 8 Gy X-radiated cells to 12.2 ± 0.9% (1.0 mmol/L-1 AA-Tempol) in AA-Tempo pretreated HUVEC cells. This implies that 1.0 mM AA-Tempol treatment significantly block the increase of caspase-3 activity in radiated HUVEC cells (P < 0.01), causing down-regulation in expressions of Bax and P53 and up-regulation in the expression of Bcl-2. Pretreatment with AA-Tempol also decreased the MDA activities (P < 0.01) and increase the GSH level (P < 0.05) in HUVEC cells compared to the 8Gy X-radiated cells without pretreatment.

CONCLUSIONS

These observations indicate that AA-Tempol is a potential therapeutic agent against the radiation damage.

Health-promoting effects of the citrus flavanone hesperidin

Hesperidin, a member of the flavanone group of flavonoids, can be isolated in large amounts from the rinds of some citrus species. Considering the wide range of pharmacological activities and widespread application of hesperidin, this paper reviews preclinical and clinical trials of hesperidin and its related compounds, including their occurrence, pharmacokinetics, and some marketed products available. Preclinical studies and clinical trials demonstrated therapeutical effects of hesperidin and its aglycone hesperetin in various diseases, such as neurological disorders, psychiatric disorders, and cardiovascular diseases and others, due to its anti-inflammatory, antioxidant, lipid-lowering, and insulin-sensitizing properties.

Radioprotective effect of hesperidin on reducing oxidative stress in the lens tissue of rats

Introduction:

Oxidative stress is a common factor in cataract. Considering the antioxidant properties of hesperidin as a flavanone glycoside from the flavonoid family with radioprotective effect, this study aimed to determine the protective effect of this flavanone glycoside on reducing oxidative stress in the eye lens tissue of mature rats caused by gamma irradiation.

Materials and Methods:

A total of 48 adult rats were randomly divided into six groups, namely, control, Dimethyl sulfoxide (DMSO), hesperidin, radiation, radiation + DMSO, and radiation + hesperidin. 15 Gy irradiation was carried out using Cobalt-60 teletherapy instrument with a source-to-surface distance of 80 cm at a dose rate of 98.5 cGy/min. 2 days following irradiation, we removed the rats' lenses and analyzed them to determine the effects of hesperidin.

Results:

The comparison of control and intervention groups after irradiation showed that malondialdehyde (MDA) level in the lens tissue was significantly higher in the irradiation groups than the control group. Furthermore, a significant difference between radiation and radiation + hesperidin groups were observed. The level of glutathione (GSH) in the lens tissue was significantly lower in the irradiation groups compared to the control group. Nonetheless, significant elevation of GSH in the radiation + hesperidin group compared to radiation group was seen.

Conclusions:

Radiation exposure reduced GSH and enhanced MDA levels in the lens tissue. However, GSH and MDA levels were modulated after hesperidin consumption. These results show the antioxidative properties of hesperidin in the lens and demonstrated that radiation complications such as cataract can be reduced by hesperidin through reducing oxidative stress.

In vitro Protective Effect of Rutin and Quercetin against Radiation-induced Genetic Damage in Human Lymphocytes

Purpose of the Study:

Rutin (RUT) and quercetin (QRT) which are dietary compounds were investigated for their ability to protect against ionizing radiation (IR)-induced genotoxicity in human lymphocytes.

Materials and Methods:

The radiation antagonistic potential of RUT and QRT was assessed by alkaline comet and cytokinesis-block micronucleus (CBMN) assay.

Results:

Treatment of lymphocytes with RUT and QRT (25 μg/ml) prior exposure to 2 Gy gamma radiation resulted in a significant reduction of frequency of micronuclei as compared to the control set of cells evaluated by CBMN assay. Similarly, treatment of lymphocytes with RUT and QRT before radiation exposure showed significant decrease in the DNA damage as assessed by comet parameters, such as percent tail DNA and olive tail moment.

Conclusion:

The study demonstrates the protective effect of RUT and QRT against IR-induced DNA damage in human lymphocytes, which may be partly attributed to scavenging of IR-induced free radicals and also by the inhibition of IR-induced oxidative stress.

Effects of Hesperidin as a Radio-protector on Apoptosis in Rat Peripheral Blood Lymphocytes after Gamma Radiation

INTRODUCTION

Hesperidin (HES), as the most abundant flavonoid existing in the citrus, is widely used by human daily. The radio-protective effects of Hesperidin have been confirmed in various measurement systems. This study aimed to evaluate the effects of Hesperidin on the changes in the apoptosis level and expression of apoptotic genes target (bax, bcl-2 and ration of bax/bcl-2) in the peripheral blood lymphocytes of male rats after gamma radiation.

MATERIALS AND METHODS

64 male rats were divided into eight groups: Control, HES (100 mg/kg b.w, orally, 7 days), whole body irradiation with 2 and 8Gy, pre-administrated with 50 and 100 mg/kg body weight of Hesperidin for 7 days before irradiation with 2 and 8 Gy. 24 hours after radiation, apoptotic lymphocytes were evaluated using PE Annexin V Apoptosis detection I kit and the levels of mRNA for bax and bcl-2 were evaluated by real time reverse transcription polymerase chain reaction.

RESULTS

A significant reduction in apoptosis of the lymphocytes was demonstrated in group animals receiving 8 Gy compared to the group which received 2 Gy irradiation (p<0.0001). However, apoptosis significantly increased in group of rats who received Hesp before irradiation (p<0.05). The increase of apoptosis by Hesperidin administration can be attributed to the decreased expression of bax and significantly reduced expression of bcl-2 and finally increasing the ration of bax/bcl-2.

CONCLUSION

The results suggest that administration of 50 and 100 mg/kg of Hesperidin induces apoptotic effects by changing expression level of bax, bcl-2 and also the ratio of bax/bcl2.

Neuroprotective effects of methane-rich saline on experimental acute carbon monoxide toxicity

BACKGROUND

Methane has been reported to play a protective role in ischemia-reperfusion injury via anti-oxidation, anti-inflammatory and anti-apoptotic activities. This study was designed to determine the protective effects of methane-rich saline (MRS) on acute carbon monoxide (CO) poisoning.

METHODS

A total of 36 male Sprague-Dawley rats were randomly divided into 3 groups: sham group, CO group and MRS group. Acute CO poisoning was induced by exposing rats to 1000ppm CO in air for 40min and then to 3000ppm CO for an additional 20min until they lost consciousness. MRS at 10ml/kg was intraperitoneally administered at 0h, 8h and 16h after CO exposure. Rats were sacrificed 24h after CO exposure. Brains were collected for Nissl staining. The cortex and hippocampus were separated for the detections of malondialdehyde (MDA), 3-nitrotyrosine (3-NT), 8-hydroxydeoxyguanosine (8-OHdG), tumor necrosis factor-α (TNF-α), interleukin1-β (IL-1β), interleukin-6 (IL-6) and superoxide dismutase (SOD) activities.

RESULTS

The results showed that MRS treatment improved neuronal injury, reduced MDA, 3-NT and 8-OHdG, and increased SOD activity of the hippocampus and cortex compared with normal saline-treated rats. In addition, MRS reduced the expression of TNF-α and IL-1β in the brain but had no effect on IL-6 expression.

CONCLUSION

These findings suggest that MRS may protect the brain against acute CO poisoning-induced injury via its anti-oxidative and anti-inflammatory activities.

Utilization of cytogenetic biomarkers as a tool for assessment of radiation injury and evaluation of radiomodulatory effects of various medicinal plants - a review

Systematic biological measurement of “cytogenetic endpoints” has helped phenomenally in assessment of risks associated with radiation exposure. There has been a surge in recent times for the usage of radioactive materials in health care, agriculture, industrial, and nuclear power sectors. The likelihood of radiation exposure from accidental or occupational means is always higher in an overburdened ecosystem that is continuously challenged to meet the population demands. Risks associated with radiation exposure in this era of modern industrial growth are minimal as international regulations for maintaining the safety standards are stringent and strictly adhered to, however, a recent disaster like “Fukushima” impels us to think beyond. The major objective of radiobiology is the development of an orally effective radio-modifier that provides protection from radiation exposure. Once available for mass usage, these compounds will not only be useful for providing selective protection against accidental and occupational radiation exposure but also help to permit use of higher doses of radiation during treatment of various malignancies curtailing unwarranted adverse effects imposed on normal tissues. Bio-active compounds isolated from natural sources enriched with antioxidants possess unique immune-modulating properties, thus providing a double edged benefit over synthetic radioprotectors. We aim to provide here a comprehensive overview of the various agents originating from plant sources that portrayed promising radioprotection in various experimental models with special emphasis on studies that used cytogenetic biomarkers. The agents will include crude extracts of various medicinal plants, purified fractions, and herbal preparations.

Protective effects of flavonoids against microbes and toxins: The cases of hesperidin and hesperetin

Many plants produce flavonoids as secondary metabolites. These organic compounds may be involved in the defense against plant-threatening factors, such as microbes and toxins. Certain flavonoids protect their origin source against plant pathogens, but they also exhibit potential healthy properties in human organisms. Hesperidin (Hsd) and its aglycone, hesperetin (Hst), are two flavonoids from the Citrus species that exhibit various biological properties, including antioxidant, antiinflammatory and anticancer effects. Recent studies indicated that Hst and Hsd possess antimicrobial activity. Although the exact mechanisms behind their antimicrobial properties are not fully understood, several mechanisms such as the activation of the host immune system, bacterial membrane disruption, and interference with microbial enzymes, have been proposed. Hsd and Hst may also have protective effects against toxicity induced by various agents. These natural substances may contribute to the protection of cells and tissues through their antioxidant and radical scavenging activities. This review discusses the protective activities of Hsd and Hst against microbes and several toxicities induced by oxidants, chemicals, toxins, chemotherapy and radiotherapy agents, which were reported in vitro and in vivo. Furthermore, the probable mechanisms behind these activities are discussed.

Alleviation of radiation-induced genomic damage in human peripheral blood lymphocytes by active principles of Podophyllum hexandrum: an in vitro study using chromosomal and CBMN assay

This study was aimed to evaluate the protection against radiation of human peripheral blood lymphocytic DNA by a formulation of three isolated active principles of Podophyllum hexandrum (G-002M). G-002M in various concentrations was administered 1h prior to irradiation in culture media containing blood. Radioprotective efficacy of G-002M to lymphocytic DNA was estimated using various parameters such as dicentrics, micronuclei (MN), nucleoplasmic bridges (NPB) and nuclear buds (NuB) in binucleated cells. Certain experiments to ascertain the G2/M arrest potential of G-002M were also conducted. It was effective in arresting the cells even at half of the concentration of colchicine used. Observations demonstrated a radiation-dose-dependent increase in dicentric chromosomes (DC), acentric fragments, MN, NPB and NuB upto 5Gy. These changes were found significantly decreased by pre-administration of G-002M. A highly significant dose modifying factor (DMF) 1.43 and 1.39 based on dicentric assay and cytokinesis block micronuclei assay, respectively, was observed against 5Gy exposure in the current experiments. G-002M alone in its effective dose did not induct any change in any of the parameters mentioned above. Observations on cell cycle arrest by G-002M showed that the formulation has potential in arresting cells at G2/M, compared with colchicine. Based on significant DMF at highest radiation dose (5Gy) studied currently and meaningful reduction in radiation-induced chromosomal aberrations, we express that G-002M has a potential of minimising radiation-induced DNA (cytogenetic) damage.

Hydrogen protects rats from dermatitis caused by local radiation

BACKGROUND

Radiation therapy produced unwanted side effect on normal tissues, such as radiodermatitis. Hydrogen was previously shown capable of radiation protective in both animals and cell cultures. The effect of hydrogen was now to be investigated on radiation-induced cutaneous.

OBJECTIVE

Development of dermatitis is a frequent side effect of radiotherapy of patients with head-and-neck cancer. Here we analyzed the radioprotective efficacy of hydrogen under conditions of local, single-dose or fractionated radiation treatment, and its possible molecular mechanisms.

METHODS

Rats received either single-dose or fractioned irradiation of the head-and-neck area with or without subcutaneous injection of hydrogen solution before irradiation. In vitro, the effect of hydrogen medium on radiation-induced cell viability, apoptosis, and biochemical assays was measured.

RESULT

Hydrogen significantly reduced the severity of dermatitis, accelerated tissue recovery, and reduced the extent of radiation-induced weight loss in rats after a single dose of 15 or 20 Gy but not 25 Gy of radiation. Hydrogen was also protective from cumulative doses of 30 Gy delivered in three fractions, respectively. Hydrogen also protect HaCaT cells from radiation-induced injury, it could significantly inhibit ionizing injury.

CONCLUSION

These results suggest that hydrogen has a positive effect on acute radiodermatitis.

Effect of hesperidin pretreatment on the expression of apoptosis-related genes in the liver of mice with acetaminophen-induced acute liver injury

AIM: To investigate the protective effect of hesperidin (HDN) pretreatment on the expression of apoptosis-related genes in the liver of mice with acetaminophen (APAP)-induced acute liver injury.

METHODS: Sixty male Balb/c mice were randomly divided into six groups, including normal group, model group, bifendate group, low-, medium-, and high-dose HDN groups. The HDN groups were intragastrically given different doses of hesperidin for 10 d. The bifendate group was given bifendate. Acute liver injury was induced by injecting APAP in all mice except those in the normal group. After 16 h, all mice were sacrificed. Liver index was calculated. Serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were measured. The activity of superoxide dismutase (SOD) and the contents of glutathione peroxidase (GSH-PX) and malondialdehyde (MDA) in liver homogenates were determined. Pathological changes in hepatic tissue were observed under an optical microscope. Apoptosis of hepatic cells was detected by TUNEL assay. The expression of Bcl-2 and Bax mRNAs in hepatic tissue was measured by reverse transcription polymerase chain reaction (RT-PCR).

RESULTS: Compared to the normal group, liver index, serum levels of ALT and AST, and the contents of MDA were significantly increased, and the activity of SOD and contents of GSH-PX in liver homogenates were significantly decreased in the model group (5.41% ± 0.68% vs 4.38% ± 0.17%, 1456.49 U/L ± 413.45 U/L vs 45.36 U/L ± 11.98 U/L, 1929.34 U/L ± 810.19 U/L vs 78.49 U/L ± 10.22 U/L, 32.04 nmol/mgprot ± 9.32 nmol/mgprot vs 11.83 nmol/mgprot ± 1.72 nmol/mgprot, 119.29 U/mgprot ± 33.02 U/mgprot vs 327.22 U/mgprot ± 26.66 U/mgprot, 75.89 μmol/L ± 20.21 μmol/Lvs 122.73 μmol/L ± 6.70 μmol/L, all P < 0.01). However, liver index, serum levels of ALT and AST, and the contents of MDA were significantly lower, and the activity of SOD and contents of GSH-PX were significantly higher in the bifendate group, high- and medium-dose HDN groups than in the model group (4.65% ± 0.61%, 4.59% ± 0.57%, 4.73% ± 0.63%vs 4.38% ± 0.17%; 66.36 U/L ± 13.43 U/L, 225.29 U/L ± 53.02 U/L, 773.06 U/L ± 251.27 U/L vs 1456.49 U/L ± 413.45 U/L; 105.75 U/L ± 17.02 U/L, 540.92 U/L ± 170.57 U/L, 906.78 U/L ± 226.38 U/L vs 1929.34 U/L ± 810.1 U/L; 15.74 nmol/mgprot ± 2.98 nmol/mgprot, 16.04 nmol/mgprot ± 4.92 nmol/mgprot, 20.85 nmol/mgprot ± 6.04 nmol/mgprot vs 32.04 nmol/mgprot ± 9.32 nmol/mgprot; 222.52 U/mgprot ± 56.11 U/mgprot, 245.95 U/mgprot ± 41.90 U/mgprot, 198.12 U/mgprot ± 68.09 U/mgprot vs 119.29 U/mgprot ± 33.02 U/mgprot; 108.70 μmol/L ± 25.96 μmol/L, 107.39 μmol/L ± 32.60 μmol/L, 98.90 μmol/L ± 10.71 μmol/L vs 75.89 μmol/L ± 20.21 μmol/L, all P < 0.01 or 0.05). The spleen index showed no significant differences among each group (all P > 0.05). Massive patchy necrosis surrounding the central vein, cellular swelling, massive inflammatory cell infiltration, and significant liver cell apoptosis were observed in liver tissues of mice in the model group; however, these pathological changes and cell apoptosis were significantly alleviated in the bifendate group and HDN groups. Such improvement was most obvious in the bifendate group and high-dose HDN group. APAP could significantly up-regulate Bax mRNA expression, down-regulate Bcl-2 mRNA expression, and decrease the Bcl-2/Bax ratio (0.68 ± 0.03 vs 0.28 ± 0.02, 0.21 ± 0.04 vs 0.58 ± 0.01; both P < 0.01). However, Bcl-2 mRNA expression was significantly up-regulated, Bax mRNA expression was significantly down-regulated and the Bcl-2/Bax ratio was significantly increased in the bifendate group, high- and medium-dose HDN groups (0.22 ± 0.04, 0.56 ± 0.01, 0.75 ± 0.01 vs 0.21 ± 0.04; 0.67 ± 0.06, 0.26 ± 0.005, 0.28 ± 0.02 vs 0.68 ± 0.03, all P < 0.05).

CONCLUSION: HDN pretreatment protects mice from acetaminophen-induced liver injury possibly via mechanisms associated with inhibiting lipid peroxidation and regulating the expressions of apoptosis-related genes.

Salvianic acid A protects L-02 cells against γ-irradiation-induced apoptosis via the scavenging of reactive oxygen species

Salvianic acid A (SAA) is the main hydrophilic active ingredient of Salvia miltiorrhiza bunge, which has long been used to treat liver and heart disease in China. In the present study, we investigated the radioprotective effects of SAA against γ-radiation-induced apoptosis in cultured human embryo liver L-02 cells. The results demonstrated that SAA markedly inhibited γ-radiation induced apoptosis, decreased DNA damage, and increased the intracellular antioxidative ability of the L-02 cells. SAA exhibited radioprotection by decreasing the generation of reactive oxygen species, inhibiting the release of mitochondrial cytochrome C, blocking the activation of caspase-3, and down regulating the expression of Bax and P53 and up regulating the expression of Bcl-2. This indicated that SAA pretreatment inhibited the caspase-dependent mitochondria apoptosis pathway. The radioprotection of the SAA pretreatment was also evidenced by an increased survival ratio, maintaining the antioxidant enzyme levels in the liver, inhibition of oxidative stress, and relative low liver and renal toxicity compared with estriol exposure. In conclusion, SAA may be an effective radioprotector against γ-radiation induced apoptosis in L-02 cells and damage in mice, the antioxidant potency of SAA might be correlated with the beneficial radioprotectant effects observed.

Radio-protective effect of catalpol in cultured cells and mice

Ionizing radiation can induce DNA damage and cell death by generating reactive oxygen species (ROS). The objective of this study was to investigate the radio-protective effect of catalpol (a main bioactive component in the traditional Chinese Rehmannia) on irradiated cells and mice. We found that treating cells with catalpol (25-100 μg/ml) before irradiation could significantly inhibit ionizing radiation (IR)-induced human lymphocyte AHH-1 cells apoptosis and increase cells viability in vitro. At the same time our study also showed that catalpol (25-100 mg/kg) reduced morphological damage of the gastrointestinal tract by 15.6%, 33.3% and 44.4%, respectively compared with the radiation-induced group, decreased plasma malondialdehyde (MDA) intestinal 8-hydroxydeoxyguanosine (8-OHdG) levels and increased plasma endogenous antioxidants and peripheral white blood cells and platelets in vivo. These results suggest that catalpol possesses notable radio-protective activity, which might be related to its effect of reducing ROS.

Radioprotection by two phenolic compounds: chlorogenic and quinic acid, on X-ray induced DNA damage in human blood lymphocytes in vitro

The present study was designed to determine the radioprotective effect of two phytochemicals, namely, quinic acid and chlorogenic acid, against X-ray irradiation-induced genomic instability in non-tumorigenic human blood lymphocytes. The protective ability of two phenolic acids against radiation-induced DNA damage was assessed using the alkaline comet assay in human blood lymphocytes isolated from two healthy human donors. A Siemens Mevatron MD2 (Siemens AG, USA, 1994) linear accelerator was used for irradiation. The results of the alkaline comet assay revealed that quinic acid and chlorogenic acid decreased the DNA damage induced by X-ray irradiation and provided a significant radioprotective effect. Quinic acid decreased the presence of irradiation-induced DNA damage by 5.99-53.57% and chlorogenic acid by 4.49-48.15%, as determined by the alkaline comet assay. The results show that quinic acid and chlorogenic acid may act as radioprotective compounds. Future studies should focus on determining the mechanism by which these phenolic acids provide radioprotection.

Radioprotective property of an aqueous extract from valeriana wallichii

Objectives:

Preparations of herbal drugs have drawn considerable interest in scientific community in recent years for the treatment of several stress related health problems including radiation-injury.

Materials and Methods:

An aqueous extract from Valeriana wallichii containing hesperidin as one of its major constituent was evaluated for its ability to protect against radiation-injury in model systems like plasmid deoxyribonucleic acid (DNA) and cultured human fibroblast cells.

Results:

The extract was found to significantly counter radiation-induced free radicals at 4 h after 5 Gy irradiation, reduced prolonged oxidative stress led increase in mitochondrial mass, enhanced reproductive viability of cultured cells and protected against radiation-induced DNA damage in solution.

Discussion:

Further studies are required to validate the radioprotective ability of the extract and to develop a safer radioprotective agent.

Protective effect of dendrodoine analog, an aminothiazole derivative against X-radiation induced hepatocellular damage in mice

This study evaluated the radioprotective effect of dendrodoine analog (DA) against radiation-induced damage in the liver of mice. The study was divided into two phases; in the first phase, the effective concentration of DA was fixed by performing a survival study. In the second phase, the fixed effective concentration of DA was orally administered to mice to evaluate its radioprotective efficacy by performing various assays. The results indicated that the radiation-induced decrease in the activities of antioxidant enzymes, increase in thiobarbituric acid reactive substances (TBARS) and comet parameters were altered by pre-administration with the effective concentration of DA which restored the antioxidant status to near normal and decreased the level of the TBARS and comet parameters. The histopathological examinations further confirmed the hepatoprotective effect of DA in mice. Thus, the current study showed DA to be an effective radioprotector against radiation induced damage in the liver of mice.

Evaluation of the intravenous and topical routes for ocular delivery of hesperidin and hesperetin

PURPOSE

The objective of this study was to determine the ocular bioavailability of hesperidin and hesperetin, especially with respect to their distribution into the posterior segment of the eye, following systemic and topical administration in rabbits.

METHODS

Hesperidin and hesperetin were administered either intravenously or topically to male New Zealand white (NZW) rabbits. Vitreous humor and plasma samples were collected after intravenous administration and analyzed to estimate the concentrations of the parent compounds and their metabolites. Ocular tissue concentrations, obtained on topical administration of hesperidin and hesperetin, were also determined.

RESULTS

In the systemic circulation, hesperidin and hesperetin were rapidly metabolized into their glucuronides, which are extremely hydrophilic in nature. Vitreal samples did not demonstrate any detectable levels of hesperidin/hesperetin following intravenous administration. Topical administration produced significant concentrations of hesperidin/hesperetin in all the ocular tissues tested at the 1 and 3 hours time points postdosing, with hesperetin showing higher levels compared to hesperidin. However, only low levels were generated in the vitreous humor. Inclusion of a penetration enhancer, benzalkonium chloride (BAK), improved the back-of-the-eye hesperetin levels.

CONCLUSIONS

Ocular delivery of hesperidin/hesperetin via the systemic route does not seem to be feasible considering the rapid generation of the hydrophilic metabolites. Topical application appears to be more promising and needs to be further developed/refined.

Intravitreal kinetics of hesperidin, hesperetin, and hesperidin G: effect of dose and physicochemical properties

Hesperidin, a flavanone glycoside, and its aglycone hesperetin are potential candidates for the treatment of diabetic retinopathy and macular edema. The objective of this study was to delineate vitreal pharmacokinetics of hesperidin and hesperetin and the hydrophilic derivative glucosyl hesperidin (hesperidin G) following intravitreal administration in anaesthetized rabbits. Concentration changes in vitreous humor were monitored using microdialysis sampling procedure. All three molecules were administered intravitreally at three dose levels (50 µL injection volume containing 1.5, 4.5, and 15 µg of the drug, resulting in a final vitreal concentration of 1, 3, and 10 µg/mL). Vitreal microdialysis samples were collected every 20 min over a period of 10 h. All three molecules exhibited linear pharmacokinetics within the dose range tested because area under the curve and maximum concentration (C(max) ) increased linearly with increasing dose and a significant difference in the elimination parameters such as clearance or half-life was not observed. The vitreal elimination half-life of these three compounds was observed to correlate with the molecular weight and lipophilicity of the molecules. The findings from this study provide practical information that will be useful in the future design of ocular drug delivery strategies for bioflavonoids.

Role of hesperetin (a natural flavonoid) and its analogue on apoptosis in HT-29 human colon adenocarcinoma cell line--a comparative study

Colon cancer is one of the serious health problems in most developed countries and its incidence rate is increasing in India. Hesperetin (HN) (3',5,7-trihydroxy-4'-methoxyflavonone) and hesperetin analogue (HA) were tested for their apoptosis inducing ability. Methyl thiazolyl tetrazolium assay revealed a dose as well as duration-dependent reduction of HT-29 (colon adenocarcinoma) cellular growth in response to HN and HA treatment. At 24 h 70 μM of HN and 32 μM of HA showed 50% reduction of HT-29 cellular growth. Acridine orange/ethidium bromide staining showed apoptotic features of cell death induced by HN and HA. Rhodamine 123 staining showed significant reduction in mitochondrial membrane potential induced by HN and HA. HN and HA induced DNA damage was confirmed by comet tail formation. Lipid peroxidation markers (TBARS) and protein oxidation marker (PCC) were significantly elevated in HN and HA treated groups. Enzymic antioxidants such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) were slightly decreased in their activities compared to control (untreated HT-29 cells). Results of Western blot analysis of apoptosis associated genes revealed an increase in cytochrome C, Bax, cleaved caspase-3 expression and a decrease in Bcl-2 expression. These findings indicate that HN and HA induce apoptosis on HT-29 via Bax dependent mitochondrial pathway involving oxidant/antioxidant imbalance.

Oxidative DNA Damage in Blood of CVD Patients Taking Detralex

The main goal of the work reported here was to determine the degree of oxidative/alkali-labile DNA damages in peripheral blood as well as in the blood stasis from varicose vein of (chronic venous disorder) CVD patients. Moreover, determination of the impact of Detralex usage on the level of (oxidative) DNA damages in CVD patients was evaluated as well.

The degree of oxidative DNA damages was studied in a group consisted of thirty patients with diagnosed chronic venous insufficiency (CVI) in the 2nd and 3rd degree, according to clinical state, etiology, anatomy and pathophysiology (CEAP), and qualified to surgical procedure. The control group consisted of normal volunteers (blood donors) qualified during standard examinations at Regional Centers of Blood Donation and Blood Therapy.

The comet assay was used for determination of DNA damages.

Analyses of the obtained results showed increase in the level of oxidative/alkali-labile DNA damages in lymphocytes originating from antebrachial blood of CVD patients as compared to the control group (Control) (p < 0.002; ANOVA). In addition, it was demonstrated that the usage of Detralex® resulted in decrease of the level of oxidative/alkali-labile DNA damages in CVD patients as compared to patients without Detralex® treatment (p < 0.001; ANOVA).

Based on findings from the study, it may be hypothesized about occurrence of significant oxidative DNA damages as the consequence of strong oxidative stress in CVD. In addition, antioxidative effectiveness of Detralexu® was observed at the recommended dose, one tablet twice daily.

Evaluating the radioprotective effect of hesperidin in the liver of Swiss albino mice

The present study was aimed to evaluate the radioprotective efficacy of hesperidin, a flavonone glycoside against X-ray radiation-induced cellular damage in the liver of Swiss albino mice. The first phase of the study was carried out to fix the effective concentration of hesperidin by performing a 30 days of survival studies using different graded doses [12.5, 25, 50 and 100mg/kg body weight] of hesperidin administered orally to mice via intragastric intubations for seven consecutive days prior to exposure of whole body radiation (10 Gy). Based on the results of survival studies, the effective dose of hesperidin was fixed which was then administered to animals orally via intragastric intubations for seven consecutive days prior to exposure of whole body radiation (4 Gy) to evaluate its radioprotective efficacy by performing various biochemical estimations, comet assay, DNA fragmentation assay and histopathological studies in the liver of Swiss albino mice. The results indicated that radiation-induced decrease in the levels of endogenous antioxidant enzymes and increase in lipid peroxidative index, DNA damage and comet parameters were altered by pre-administration with the effective dose of hesperidin [25mg/kg body weight] which restored the antioxidant status to near normal and decreased the levels of lipid peroxidative index, DNA damage and comet parameters. These results were further confirmed by histopathological examinations which indicated that pre-administration with the effective dose of hesperidin reduced the hepatic damage induced by radiation. Thus the current study shows hesperidin to be an effective radioprotector against radiation induced damage in the liver of mice.

Gamma-ray irradiation impairs dendritic cell migration to CCL19 by down-regulation of CCR7 and induction of cell apoptosis

Dendritic cells (DCs) are the most potent antigen-presenting cells and play a crucial role in the regulation of immune response and migration of DCs into secondary lymphoid tissues also play an important role in the initiation of innate and adaptive immunity. Radiation therapy is now a routine treatment for certain types of cancer and over 20 percent of cancer patients will require radiation therapy during the treatment of their disease. However, the influence of ionizing irradiation on the migratory ability of DCs is largely unknown. In this article, we report that γ ray irradiation can significantly inhibit LPS-triggered up regulation of CCR7 expression and PGE2 production by DC, thus impairing DC migration towards CCL19 in vitro and in vivo. Moreover, γ ray exposed DC also displayed an increased apoptosis rate and decreased cell viability. Furthermore, we demonstrate that exogenous PGE2 can partly reduce the gamma-ray induced migratory impairment and restored CCR7 expression of DC. Our work suggests that γ irradiation affects DC function at multiple steps during the immune response including DC migration, and that PGE2, via control of CCR7 expression, is an important regulator of DC migration.

Hesperidin upregulates heme oxygenase-1 to attenuate hydrogen peroxide-induced cell damage in hepatic L02 cells

Hesperidin, a naturally occurring flavonoid presents in fruits and vegetables, has been reported to exert a wide range of pharmacological effects that include antioxidant, anti-inflammatory, antihypercholesterolemic, and anticarcinogenic actions. However, the cytoprotection and mechanism of hesperidin to neutralize oxidative stress in human hepatic L02 cells remain unclear. In this work, we assessed the capability of hesperidin to attenuate hydrogen peroxide (H(2)O(2))-induced cell damage by augmenting the cellular antioxidant defense. Real-time quantitative polymerase chain reaction, Western blot, and enzyme activity assay demonstrated that hesperidin upregulated heme oxygenase-1 (HO-1) expression to protect hepatocytes against oxidative stress. In addition, hesperidin also promoted nuclear translocation of nuclear factor erythroid 2-related factor (Nrf2). What's more, hesperidin exhibited activation of extracellular signal-regulated protein kinase 1/2 (ERK1/2). Besides, ERK1/2 inhibitor significantly inhibited hesperidin-mediated HO-1 upregulation and Nrf2 nuclear translocation. Taken together, the above findings suggested that hesperidin augmented cellular antioxidant defense capacity through the induction of HO-1 via ERK/Nrf2 signaling. Therefore, hesperidin has potential as a therapeutic agent in the treatment of oxidative stress-related hepatocyte injury and liver dysfunctions.