Mitigating Acetaminophen-Induced Hepatotoxicity by Using a Water-Alcohol Extract of Phellinus caryophylli (Agaricomycetes) in a Murine Model.

This study investigates the hepatoprotective effect of a water-alcohol extract of the medicinal mushroom Phellinus caryophylli (Racib.) G. Cunn. (PCE) against acetaminophen (APAP)-induced hepatotoxicity in Swiss albino mice. The mice orally received APAP (150 mg/kg body weight), followed by PCE extract (250 or 500 mg/kg body weight). The liver damage induced by APAP was analyzed on the basis of blood serum parameters (glutamate pyruvate transaminase, glutamate oxaloacetate transaminase, and alkaline phosphatase), antioxidant assays (reduced glutathione and glutathione peroxidase), and tissue peroxidation based on malondialdehyde level. The molecular mechanism underlying the prevention of APAP-induced damage by PCE was also analyzed. Liver damage was confirmed on the basis of increased serum parameter values, decreased antioxidant levels, and cellular and molecular alterations, which PCE restored in a dose-dependent manner. At a transcriptional level, PCE downregulated expression of the preapoptototic gene Bax and the inflammatory gene Cox2 but upregulated the antiapoptotic gene Bcl2 in the mice that received APAP. PCE exerted a hepatoprotective effect by preventing apoptotic and inflammatory events caused by APAP. Thus, this study demonstrates a hepatoprotective effect of PCE, which could be explored further for managing hepatopathy.

Reduction of Gamma Radiation-Induced Damage by Hydro-Alcoholic Extract of Nardostachys jatamansi.

The search for a nontoxic radioprotector has not yielded any promising results. Many antioxidant compounds, though effective under in vitro conditions as radioprotectors, have failed under in vivo settings due to their toxicity. The Indian medical system of Ayurveda uses a variety of plants with antioxidant potential, and these may be harboring molecules with radioprotective properties. In the present work, the radioprotective property of Nardostachys jatamansi was investigated. A hydro-alcoholic extract of this plant provided protection to the cellular DNA and membrane from 4 Gy gamma radiation. Depletion of cellular antioxidant status was also prevented by this extract. Molecular-level analysis in the intestines of mice revealed a lower bax/bcl2 ratio suggestive of a reduction of radiation-induced apoptosis. Expression levels of the DNA repair gene atm were elevated, along with a reduction in the expression of the inflammatory gene cox2. The extract also provided a survival advantage to mice exposed to lethal doses of gamma radiation. These results suggest a possible radioprotective role for Nardostachys jatamansi.

Mitigation of whole-body gamma radiation-induced damages by Clerodendron infortunatum in mammalian organisms.

Several phytoceuticals and extracts of medicinal plants are reported to mitigate deleterious effects of ionizing radiation. The potential of hydro-alcoholic extract of Clerodendron infortunatum (CIE) for providing protection to mice exposed to gamma radiation was investigated. Oral administration of CIE bestowed a survival advantage to mice exposed to lethal doses of gamma radiation. Radiation-induced depletion of the total blood count and bone marrow cellularity were prevented by treatment with CIE. Damage to the cellular DNA (as was evident from the comet assay and the micronucleus index) was also found to be decreased upon CIE administration. Radiation-induced damages to intestinal crypt cells was also reduced by CIE. Studies on gene expression in intestinal cells revealed that there was a marked increase in the Bax/Bcl-2 ratio in mice exposed to whole-body 4 Gy gamma radiation, and that administration of CIE resulted in significant lowering of this ratio, suggestive of reduction of radiation-induced apoptosis. Also, in the intestinal tissue of irradiated animals, following CIE treatment, levels of expression of the DNA repair gene Atm were found to be elevated, and there was reduction in the expression of the inflammatory Cox-2 gene. Thus, our results suggest a beneficial use of Clerodendron infortunatum for mitigating radiation toxicity.

Protective effect of ayurvedic formulations against doxorubicin-induced cardiotoxicity: Preliminary studies on Brahma Rasayana and Chyavanaprash.

AIM OF STUDY: The present work aimed to examine the efficacy of two ayurvedic formulations, Brahma Rasayana (BRM) and Chyavanaprash (CHM) to alleviate doxorubicin (DOX) induced acute cardiotoxicity. MATERIALS AND METHODS: Swiss albino mice were administered with DOX (25 mg/kg, i.p.) and two doses of BRM or CHM (1 and 2 g/kg). Cardiotoxicity was assessed by measuring the levels of various antioxidant parameters in the heart as well as release of marker enzymes in the serum was assayed. Histology of the heart was also performed to check for DOX-induced damages. RESULTS: Administration of either BRM or CHM (1 and 2 g/kg) maintained the antioxidant status in the heart thereby preventing tissue damage as well as the release of marker enzymes. DOX-induced variation of cardiac architecture was also prevented by BRM and CHM administration. CONCLUSION: BRM and CHM administration could prevent DOX-induced acute cardiotoxicity.

Amelioration of doxorubicin induced cardio-and hepato-toxicity by carotenoids.

AIM OF STUDY: The aim of this study is to explore the ability of the carotenoids (CARs) to offer protection against acute cardiotoxicity and hepatotoxicity induced by doxorubicin (DOX) (25 mg/kg) in tumor bearing Swiss albino mice. MATERIALS AND METHODS: Tumor bearing Swiss albino mice administered with DOX (25 mg/kg, i.p) and two doses of CARs (50 and 100 µg/kg). 24 h after administration of the drugs, histopathological evaluation of tumor, liver and heart tissues carried out. Furthermore, various antioxidant parameters in these tissues were investigated. Serum marker enzymes for tissue injury were examined. RESULTS: Administration of CARs prevented the depletion of antioxidants in the heart and liver, thereby protecting the tissue damage and release of marker enzymes. However, similar antioxidant depletion was not observed in the tumor tissue. CARs prevented DOX induced variation in tissue architecture in heart and liver tissues. However, CARs did not influence DOX induced alterations in the tumor. CONCLUSION: Administration of CARs could prevent DOX induced acute toxicity to heart and liver.

Sanazole directed targeting of silver nanoparticle drug complex to tumor mass: a preclinical investigation in murine model.

AIM OF STUDY: To explore sanazole (AK) directed targeting of the antineoplastic drug doxorubicin (DOX) complexed with silver nanoparticles (SNs) to tumor growth in a murine model. MATERIALS AND METHODS: Sanazole (AK) and DOX were complexed with SNs, individually and in combination to obtain SN-AK, SN-DOX, and SN-AK-DOX. Solid tumors were developed on hind limbs of Swiss albino mice by transplanting Dalton's lymphoma ascitess (DLAs) tumor cells. Induction of cytotoxicity and apoptosis in the DLA cells by AK and DOX complexed with SN, individually and in combination, were examined under in vitro conditions by incubating the cells with them. SN, AK, DOX, SN-AK, SN-DOX, AK-DOX, and SN-AK-DOX were administered orally to the tumor bearing mice and the therapeutic efficacy of AK-directed targeting of SN-DOX complexes to achieve tumor control was monitored. RESULTS: Under in vitro conditions, SN, AK, DOX, SN-AK, SN-DOX, AK-DOX, and SN-AK-DOX induced cytotoxicity and apoptosis in DLA cells to varying extents. The SN-AK-DOX complex showed higher level of cytotoxicity and apoptosis-induction in DLA cells. Similarly, administration of SN, AK, DOX, SN-AK, SN-DOX, AK-DOX, and SN-AK-DOX resulted in significant reduction in tumor volume and delay in tumor growth. The animals treated with SN-AK-DOX had the highest reduction in tumor volume and tumor growth. In fact, the tumor was almost absent in the animals of this group after the treatment. CONCLUSION: The SN complex of sanazole and doxorubicin together (SN-AK-DOX) has high anticancer activity under in vivo conditions and has great potential in tumor therapy.

Ascorbic acid glucoside reduces neurotoxicity and glutathione depletion in mouse brain induced by nitrotriazole radiosensitazer.

AIM: To investigate the potential of the anti-oxidant ascorbic acid glucoside (AA-2G) to modulate neurotoxicity induced by high doses of nitrotriazole radiosensitizer. MATERIALS AND METHODS: Male and female C56Bl/6xCBA hybrid mice aged 8-14 weeks (weight 18-24 g) were used. Nitrotriazole drug radiosensitizer sanazole at a high dose of 2, 1 g/kg was per os administered to induce neurotoxicity at mice. Ascorbic acid glucoside was given 30 min before the sanazole administration. Serum ascorbic acid, brain glutathione level, as well as behavioral performance using open field apparatus were measured. RESULTS: Administration of high (non-therapeutic) doses of the nitrotriazole drug sanazole results in neurotoxicity in mice as evidenced from behavioral performance, emotional activity and depletion of the cellular antioxidant, glutathione, in the brain. The serum levels of ascorbic acid was also found reduced in high dose sanazole treated animals. Per os administration of ascorbic acid glucoside significantly reduced the neurotoxicity. This effect was associated with the prevention of glutathione depletion in mouse brain and restoring the ascorbic acid level in serum. CONCLUSION: Administration of ascorbic acid glucoside, but not ascorbic acid, before sanazole administration protected from sanazole-induced neurotoxicity by preventing the decrease in the brain reduced glutathione level and providing high level of ascorbic acid in plasma.

Radioprotective effects of gallic acid in mice.

Radioprotecting ability of the natural polyphenol, gallic acid (3,4,5-trihydroxybenzoic acid, GA), was investigated in Swiss albino mice. Oral administration of GA (100 mg/kg body weight), one hour prior to whole body gamma radiation exposure (2-8 Gy; 6 animals/group), reduced the radiation-induced cellular DNA damage in mouse peripheral blood leukocytes, bone marrow cells, and spleenocytes as revealed by comet assay. The GA administration also prevented the radiation-induced decrease in the levels of the antioxidant enzyme, glutathione peroxidise (GPx), and nonprotein thiol glutathione (GSH) and inhibited the peroxidation of membrane lipids in these animals. Exposure of mice to whole body gamma radiation also caused the formation of micronuclei in blood reticulocytes and chromosomal aberrations in bone marrow cells, and the administration of GA resulted in the inhibition of micronucleus formation and chromosomal aberrations. In irradiated animals, administration of GA elicited an enhancement in the rate of DNA repair process and a significant increase in endogenous spleen colony formation. The administration of GA also prevented the radiation-induced weight loss and mortality in animals (10 animals/group) exposed to lethal dose (10 Gy) of gamma radiation. (For every experiment unirradiated animals without GA administration were taken as normal control; specific dose (Gy) irradiated animals without GA administration serve as radiation control; and unirradiated GA treated animals were taken as drug alone control).

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.

Studies on silver nanoparticle-glycyrrhizic acid complex as a radioprotector and an adjuvant in radiotherapy under in vivo conditions.

Silver nanoparticles (SN) of particle size of less than 50 nm were dispersed in an aqueous solution of Pluronic F127 and complexed with the phytoceutical, glyzyrrhizic acid (GLY). Radioprotecting ability of the obtained nanoparticle-glyzyrrhizic acid complex (SN-GLY) was evaluated in an in vivo model using Swiss albino mice. The potential of the complex as an adjuvant during radiotherapy was also analyzed in tumor-bearing mice. The administration of SN-GLY, SN, and GLY protected the hemopoetic and gastrointestinal system against radiation-induced damages as revealed by the total white blood cell count, bone marrow cellularity, endogenous spleen colony formation, levels of cellular antioxidants, and histopathologcal examination of gastrointestinal tract. Oral administration of SN-GLY, SN, and GLY 1 hour before a sublethal dose of radiation exposure reduced the radiation-induced depletion of cellular antioxidants and lipid peroxidation in various tissues of mice. Survival of animals following exposure to a lethal dose of gamma radiation was also improved. It was also found that the oral administration of the complex to tumor-bearing mice before 4 Gy gamma irradiation resulted in a faster tumor regression.

Prevention of γ-radiation induced cellular genotoxicity by tempol: protection of hematopoietic system.

Tempol (TPL) under in vitro conditions reduced the extent of gamma radiation induced membrane lipid peroxidation and disappearance of covalently closed circular form of plasmid pBR322. TPL protected cellular DNA from radiation-induced damage in various tissues under ex vivo and in vivo conditions as evidenced by comet assay. TPL also prevented radiation induced micronuclei formation (in peripheral blood leucocytes) and chromosomal aberrations (in bone marrow cells) in whole body irradiated mice. TPL enhanced the rate of repair of cellular DNA (blood leucocytes and bone marrow cells) damage when administered immediately after radiation exposure as revealed from the increased Cellular DNA Repair Index (CRI). The studies thus provided compelling evidence to reveal the effectiveness of TPL to protect hematopoietic system from radiation injury.

Protection from lethal and sub-lethal whole body exposures of mice to γ-radiation by Acorus calamus L.: studies on tissue antioxidant status and cellular DNA damage.

The radioprotecting activity of Acorus calamus extract after whole body exposure of mice to lethal and sub-lethal doses of γ-irradiation in terms of radiation induced mortality and damages to cellular DNA and tissue antioxidant levels were studied. A. calamus extract (250 mg/kg body weight) was orally administered to mice 1 h prior to whole body γ-radiation exposure. The antioxidant levels in the tissue homogenates of brain, liver and kidney of the irradiated mice were determined and cellular DNA damage was monitored by comet assay. Effect of administration of the extract on survival of the animals exposed to acute lethal dose of 10 Gy whole body γ-radiations was also monitored. Administration of the extract significantly increased the activities of major enzymes of the antioxidant defense system specially SOD, catalase and GPx and levels of GSH in 2, 6 and 10 Gy irradiated mice and decreased the formation MDA. The extract also decreased DNA strand breaks. The survival rate was found to be increased up to 5%. These studies highlight the role of A. calamus extract as good source of natural radioprotecting agent and its therapeutic implications for radiation-induced injuries.

Hepatoprotective activity of Andrographis paniculata and Swertia chirayita.

Andrographis paniculata (Family: Acanthaceae) and Swertia chirayita (Family: Gentianaceae) are two controversial medicinal plants used as Kiriyattu, having similar therapeutic action and are used as a hepatoprotective and hepatostimulative agent. A. paniculata grows in southern parts of India and S. chirayita in the Himalayan region. The present work concerns on the ability of the extracts of these plants to offer protection against acute hepatotoxicity induced by paracetamol (150 mg/kg) in Swiss albino mice. Oral administration of A. paniculata or S. chirayita extract (100-200mg/kg) offered a significant dose dependent protection against paracetamol induced hepatotoxicity as assessed in terms of biochemical and histopathological parameters. The paracetamol induced elevated levels of serum marker enzymes such as serum glutamate pyruvate transaminase (GPT), serum glutamate oxaloacetate transaminase (GOT), alkaline phosphatase (ALP), and bilirubin in peripheral blood serum and distorted hepatic tissue architecture along with increased levels of lipid peroxides (LPO) and reduction of superoxide dismutase (SOD), catalase, reduced glutathione (GSH) and glutathione peroxidase (GPx) in liver tissue. Administration of the plant extracts after paracetamol insult restored the levels of these parameters to control (untreated) levels. Thus the present study revealed that the extracts of A. paniculata or S. chirayita offered protection against hepatotoxicity induced by paracetamol.

Protection against genotoxic damages following whole body gamma radiation exposure in mice by lipoic acid.

Alpha-lipoic acid (LA) protected plasmid pBR 322 DNA, under in vitro conditions from gamma radiation induced strand breaks as evidenced by the prevention of the loss of supercoiled covalently closed circular form upon irradiation. It also protected the membrane lipids of liver homogenates from the oxidative damages. Whole body exposure of mice to gamma-radiation resulted in damage to cellular DNA in various tissues and administration of LA prior to the radiation exposure prevented the radiation induced DNA damage as assessed by alkaline comet assay. Administration of LA to mice prior to the radiation exposure also prevented induction of chromosomal damages in bone marrow cells and formation of micronuclei in blood reticulocytes. Thus taken together, LA a normal cellular constituent could be used as a radioprotector against whole body radiation exposure scenarios.

Cellular radioprotecting potential of glyzyrrhizic acid, silver nanoparticle and their complex.

Silver nanoparticles (SN) of particle size of less than 50nm were redispersed in aqueous solution of Pluronic F127 and complexed with the phytoceutical, glyzyrrhizic acid (GLY). Radioprotecting ability of the obtained nanoparticle-glyzyrrhizic acid complex (SN-GLY) was evaluated in an in vivo model using Swiss albino mice. Oral administration of SN-GLY, SN and GLY one hour prior to radiation exposure reduced the radiation induced damage in peripheral blood leucocytes, bone marrow cells and spleen cells of mice as revealed by comet assay. Exposure of mice to whole body gamma irradiation resulted in formation of micronuclei in blood reticulocytes and chromosomal aberrations in bone marrow cells while SN-GLY, SN or GLY administration resulted in reduction in micronucleus formation and chromosomal aberrations indicating radioprotection. In SN-GLY treated mice the cellular DNA was found protected to a greater extent compared to GLY or SN treated mice. The studies, under in vivo radiation exposure conditions, showed effective radiation protection.

Synthesis of nanosilver using a vitamin C derivative and studies on radiation protection.

Silver nanoparticles were prepared from silver nitrate using a vitamin C derivative, 6-palmitoyl ascorbic acid-2-glucoside (PAsAG), via a sonochemical experiment. The resultant golden yellow solution that contained silver nanoparticle-PAsAG complex (SN-PAsAG) of about 5 nm particle sizes was explored for its potential to offer protection to DNA from γ-radiation-induced damages. The presence of SN-PAsAG during irradiation inhibited the disappearance of covalently closed circular (ccc) form of plasmid pBR322 with a dose modifying factor of 1.78. SN-PAsAG protected cellular DNA from radiation-induced damage as evident from comet assay study on mouse spleen cells, irradiated ex vivo. When orally administered with SN-PAsAG at 1 hour prior to whole-body radiation exposure, cellular DNA was found protected from radiation-induced strand breaks in various tissues (spleen cells, bone marrow cells, and blood leucocytes) of animals. Also, SN-PAsAG could enhance the rate of repair of cellular DNA in blood leucocytes and bone marrow cells when administered immediately after radiation exposure. The studies, under in vitro, ex vivo, and in vivo radiation exposure conditions, showed effective radiation protection.

Radioprotection by α-asarone: prevention of genotoxicity and hematopoietic injury in mammalian organism.

α-Asarone (1-propenyl-2,4,5-methoxybenzol), one of the active components of Acorus calamus extract, was examined for its efficacy as a radioprotector in mice exposed to lethal and sublethal whole-body γ-radiation. Oral administration of α-asarone 1h prior to the radiation exposure reduced radiation induced alterations in the endogenous antioxidant defense systems. The radiation induced cellular DNA damages as revealed by comet assay, micronuclei formation and chromosomal aberrations were also significantly reduced following the asarone treatment. α-Asarone administration enhanced the endogenous spleen colony formation and reduced radiation-induced mortality and facilitated recovery from the radiation-induced loss of body weight in mice surviving after 8Gy γ-radiation exposure. These studies highlight the role of α-asarone as a good natural radioprotecting agent with therapeutic implications in case of radiation-exposure scenarios.

Radioprotection by alpha-lipoic acid palladium complex formulation (POLY-MVA) in mice.

The dietary supplement, POLY-MVA, containing palladium alpha-lipoic acid complex was examined for its efficacy as a radioprotector in mice exposed to whole-body gamma-radiation. Oral administration of POLY-MVA enhanced endogenous spleen colony formation in animals exposed to a sublethal dose of 6 Gy gamma-radiation. Alkaline comet assay revealed that the nuclear DNA comet parameters such as percent DNA in tail, tail length, tail moment, and olive tail moment, of the bone marrow cells and spleen cells, were found increased following whole-body gamma-irradiation. The radiation-induced DNA damage in these cells was reduced when POLY-MVA was administered to animals exposed to a lethal dose of 8 Gy whole-body gamma-radiation. The administration of POLY-MVA significantly reduced the gamma-radiation-induced mortality and also aided recovery from the radiation-induced loss of body weight in mice surviving after 8 Gy gamma-radiation exposure. These results suggest the potential use of POLY-MVA as a radioprotector in cases of planned radiation exposures.

Protection of cellular DNA and membrane from γ-radiation-induced damages and enhancement in DNA repair by sesamol.

Sesamol (SM), a nutritional phenolic antioxidant compound present in sesame seeds, protected pBR 322 DNA from gamma radiation-induced damages. SM prevented gamma radiation-induced degradation of covalently closed circular form of plasmid DNA in a concentration-dependent manner. Also SM protected cellular DNA of mouse blood leukocytes exposed to 4 Gy gamma radiation, ex vivo, as revealed by the data from alkaline comet assay studies. SM (5 mM) showed a faster time-dependant decrease of the radiation-induced DNA damage in mouse blood leukocytes following postirradiation incubation ex vivo, which could be attributed to enhanced DNA repair. SM protected the biomembranes from radiation-induced lipid peroxidation. Thus, SM could act as a radioprotector for the biomembranes and cellular DNA against the deleterious effects of ionizing radiation.

Protection of DNA and membrane from γ-radiation induced damage by the extract of Acorus calamus Linn.: An in vitro study.

Acorus calamus, an ethnomedicinally important plant, was investigated for its protecting activity against radiation induced DNA and membrane damage. The in vitro free radical scavenging activity of the extract (water:ethanol, 1:1) of A. calamus was studied by parameters viz DPPH (1,1-diphenyl-2-picryl-hydrazyl) radical scavenging activity, hydroxyl radical scavenging activity, and superoxide radical scavenging activity. Membrane damage due to radiation exposure was measured as the peroxidation of lipids in terms of thiobarbituric acid reacting substance (TBARS). The in vitro DNA damage was monitored by assessing the radiation induced relaxation of supercoiled plasmid DNA (pBR322). Damage to cellular DNA induced by γ-radiation (6Gy) was monitored by alkaline single cell gel electrophoresis or comet assay in murine cells and human peripheral blood leukocytes. Enhancement of DNA repair mechanism was also monitored. The extract effectively scavenged free radicals in a concentration dependent manner. Presence of A. calamus extract during irradiation prevented peroxidation of membrane lipids in mouse liver homogenate. It helped to reduce the disappearance of the covalently closed circular (ccc) form of plasmid DNA following exposure to γ-radiation. Also the A. calamus extract effectively protected DNA from radiation induced strand breaks and enhanced the DNA repair process. Hence A. calamus extract can be used as a good source of natural radioprotecting agent.