Sources of reactive oxygen species 

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... results in Fig.1 show that allicin, which is the principal constituent of the extract, formed from its precursor allin via enzymatic degradation when crushed and macerated, destroyed the cellular structure releasing the antimutagens. The toxicity of divalent lead ions to the animals is caused by its binding to thiol or suflhydryl group; thus, inhibiting some enzymatic reactions in the body tissue [15]. Hence, the significant reduction of the mutagenic effects of lead by crude garlic extract could be attributed to the activity of ...

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... addition of cucurbits extract to the stressed neutrophils led to enhancement of free radical scavenging activity (Fig.1). This activity of cucurbits may be attributed to the phenolic compounds like flavonoids [25][26][27][28] which are known to act as antioxidants because of the donation of an electron or hydrogen atom [29]. The increase in concentrations of different cucurbit extracts (from 0.01 to 0.08 mg/ml) quenched the superoxide radicals in stressed neutrophils in a proportionate manner. Further increase in the concentration of cucurbit extracts (0.12 mg/ml) however did not inhibit the superoxide radicals in an increasing order. It appears that active biomolecules up to in 0.08 mg/ml of the cucurbit extracts scavenged superoxide radicals in stressed neutrophils almost completely ( Fig.1). At 0.12 mg/ml the presence of some other molecules in the whole extract did not enhance the effect and rather decreased in this context bringing down the SOD activity in comparison to the 0.08 mg/ml ...

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... addition of cucurbits extract to the stressed neutrophils led to enhancement of free radical scavenging activity (Fig.1). This activity of cucurbits may be attributed to the phenolic compounds like flavonoids [25][26][27][28] which are known to act as antioxidants because of the donation of an electron or hydrogen atom [29]. The increase in concentrations of different cucurbit extracts (from 0.01 to 0.08 mg/ml) quenched the superoxide radicals in stressed neutrophils in a proportionate manner. Further increase in the concentration of cucurbit extracts (0.12 mg/ml) however did not inhibit the superoxide radicals in an increasing order. It appears that active biomolecules up to in 0.08 mg/ml of the cucurbit extracts scavenged superoxide radicals in stressed neutrophils almost completely ( Fig.1). At 0.12 mg/ml the presence of some other molecules in the whole extract did not enhance the effect and rather decreased in this context bringing down the SOD activity in comparison to the 0.08 mg/ml ...

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... acetate-induced chromosomal aberrations such as chromosomes and chromatic breaks, gap and chromosomal rearrangement were analyzed. Fig.1 shows the frequencies of total chromosomal aberrations and the mean frequencies per cell as well as percentage of damaged cells in rats exposed to lead acetate in ...

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... of cancer is a multistage process requiring the cumulative action of multiple events that occur in one cell clone. The role of free radicals in carcinogenesis and their contribution to the initiation and progression of the cancer process is well established [25]. The overall process includes a three stage model: -first (initiation), a permanent change occurs in the genetic material (one somatic cell); -secondly (promotion), the mutated cell clone expants; -and finally (progression), malignant conversion into cancer develops ...

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... is a multi-step process leading a cell from normal to pre-cancerous stage and finally to an early stage of cancer [2]. Cancer development is characterized by cumulative action of multiple events occurring in a single cell and can be described as initiation, promotion and progression. Free radicals can acts in all the stages of carcinogenesis [24] (Fig.1). In view of these facts, the present review describes the role of various types of free radicals or reactive species and their defense mechanisms in gynecological cancers. In addition to this, efforts have also been made to predict new-fangled approaches include gene therapy to produce more antioxidants, genetically engineered plant products with increased levels of antioxidants, artificial antioxidant enzymes, biomolecules with antioxidant and the use of functional foods enriched with ...

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... activity: Concentration of catalase in serum, liver and lung of differentially treated experimental mice is expressed in Fig.8. We observed continuous regression in catalase activity in serum, liver and lung of irradiated mice, measured at 24h, 72h and 5 th day of study. G-002M pre-treatment, though significantly countered the fall in catalase activity at all the time points in all studied tissues (serum, liver and lung), still the values are not comparable to controls. G-002M treatment alone did not induce any variation in catalase activity studied at all the time points and in all studied tissues. Reduced glutathione; Fig.9 expresses the level of GSH in differentially treated mice sacrificed at 24 h, 72 h and 5 th day. In irradiated group, we found constant fall in GSH concentration in blood, liver and lung, studied at different time intervals. G-002M pre-treatment could significantly enhance GSH level when compared in serum, liver and lung of irradiated animals. However, the values of GSH were still less on 5 th day of study when compared with controls. G-002M alone did not induce any effect on GSH level of treated mice at any time interval. Glutathione reductase; Fig.10 depicts GR activity of serum, liver and lung tissues of differentially treated experimental mice. Radiation exposure significantly declined GR activity at all the time points of study. Fall was continuous up to 5 th day. G-002M pre-treatment could enhance the activity of this enzyme in comparison to irradiated mice; however, the concentration still could not reach the control level even on 5 th day of study. G-002M treatment alone did not alter GR activity at any time point of study in any of the studied tissues. Glutathione S-transferase; GST activity in serum, liver and lung of experimental mice is shown in Fig.11. Radiation has significantly declined the activity of this enzyme at all the time intervals of study in all the three tissues. The regression of GST in this group was constantly increased upto 5 th day of the study. G-002M treatment alone did not induce any alteration in GST activity in any of the tissue studied currently. G-002M pre-treatment could significantly counter the activity of this enzyme at all the time points in all the tissues; however, the values were not comparable to the controls at any time interval even on 5 th day of study. Table 1 reflects the levels of CHO, HDL, LDL, TG, ALP, AST, ALT, LDH, TP and albumin in sera of differentially treated experimental mice. We observed that radiation exposure could significantly decrease the level of CHO, HDL, LDL, TG and ALP on 5 th day of experimentation. The values of AST (148.80 ± 8.66 U/l and 112.07 ± 7.8 in irradiated and control groups, respectively; P < 0.01), ALT (86.65 ± 3.15 IU/l and 62.5 ± 5.01 in irradiated and control groups, Mice were dissected at different time intervals. Experiments were performed in triplicate with 3 animals in each group. Tissues homogenates were prepared from excised lungs and liver. The enzyme activity measured at 570 nm, is expressed as U/mg protein in tissues and U/ml x 10 in serum. Error bars are SEM for n = 9. a R vs C of the respective tissue; b 24 h DR vs R of the respective tissue; c 72 h DR vs R of the respective tissue; d 5 th day DR vs R of the respective tissue. *P < 0.01, **P < 0.001. Figure 9. GSH level in differentially treated mice. Mice were dissected at different time intervals. Experiments were performed in triplicate with 3 animals in each group. Tissues homogenates were prepared from excised lungs and liver. Glutathione concentration measured at 412 nm, is expressed as µM GSH/mg protein in tissues and µM GSH/ml x 10 2 in blood. The experiment was performed in triplicate with 3 animals in each group. Error bars are SEM for n = 9. a R vs C of the respective tissue; b 24 h DR vs R of the respective tissue; c 72 h DR vs R of the respective tissue; d 5 th day DR vs R of the respective tissue. *P < 0.01, **P < 0.001, NS = not significant. GST activity in differentially treated mice. Mice were dissected at different time intervals. Experiments were performed in triplicate with 3 animals in each group. Tissues homogenates were prepared from excised lungs and liver. GST activity measured at 340 nm is expressed as mM GSH-CDNB conjugate formed/min/mg protein in tissues and mM GSH-CDNB conjugate formed/min/ml x 10 -2 in serum. Error bars are SEM for n = 9. a R vs C of the respective tissue; b 24 h DR vs R of the respective tissue; c 72 h DR vs R of the respective tissue; d 5 th day DR vs R of the respective tissue. *P < 0.01, **P < 0.001, NS = not ...

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... activity: Concentration of catalase in serum, liver and lung of differentially treated experimental mice is expressed in Fig.8. We observed continuous regression in catalase activity in serum, liver and lung of irradiated mice, measured at 24h, 72h and 5 th day of study. G-002M pre-treatment, though significantly countered the fall in catalase activity at all the time points in all studied tissues (serum, liver and lung), still the values are not comparable to controls. G-002M treatment alone did not induce any variation in catalase activity studied at all the time points and in all studied tissues. Reduced glutathione; Fig.9 expresses the level of GSH in differentially treated mice sacrificed at 24 h, 72 h and 5 th day. In irradiated group, we found constant fall in GSH concentration in blood, liver and lung, studied at different time intervals. G-002M pre-treatment could significantly enhance GSH level when compared in serum, liver and lung of irradiated animals. However, the values of GSH were still less on 5 th day of study when compared with controls. G-002M alone did not induce any effect on GSH level of treated mice at any time interval. Glutathione reductase; Fig.10 depicts GR activity of serum, liver and lung tissues of differentially treated experimental mice. Radiation exposure significantly declined GR activity at all the time points of study. Fall was continuous up to 5 th day. G-002M pre-treatment could enhance the activity of this enzyme in comparison to irradiated mice; however, the concentration still could not reach the control level even on 5 th day of study. G-002M treatment alone did not alter GR activity at any time point of study in any of the studied tissues. Glutathione S-transferase; GST activity in serum, liver and lung of experimental mice is shown in Fig.11. Radiation has significantly declined the activity of this enzyme at all the time intervals of study in all the three tissues. The regression of GST in this group was constantly increased upto 5 th day of the study. G-002M treatment alone did not induce any alteration in GST activity in any of the tissue studied currently. G-002M pre-treatment could significantly counter the activity of this enzyme at all the time points in all the tissues; however, the values were not comparable to the controls at any time interval even on 5 th day of study. Table 1 reflects the levels of CHO, HDL, LDL, TG, ALP, AST, ALT, LDH, TP and albumin in sera of differentially treated experimental mice. We observed that radiation exposure could significantly decrease the level of CHO, HDL, LDL, TG and ALP on 5 th day of experimentation. The values of AST (148.80 ± 8.66 U/l and 112.07 ± 7.8 in irradiated and control groups, respectively; P < 0.01), ALT (86.65 ± 3.15 IU/l and 62.5 ± 5.01 in irradiated and control groups, Mice were dissected at different time intervals. Experiments were performed in triplicate with 3 animals in each group. Tissues homogenates were prepared from excised lungs and liver. The enzyme activity measured at 570 nm, is expressed as U/mg protein in tissues and U/ml x 10 in serum. Error bars are SEM for n = 9. a R vs C of the respective tissue; b 24 h DR vs R of the respective tissue; c 72 h DR vs R of the respective tissue; d 5 th day DR vs R of the respective tissue. *P < 0.01, **P < 0.001. Figure 9. GSH level in differentially treated mice. Mice were dissected at different time intervals. Experiments were performed in triplicate with 3 animals in each group. Tissues homogenates were prepared from excised lungs and liver. Glutathione concentration measured at 412 nm, is expressed as µM GSH/mg protein in tissues and µM GSH/ml x 10 2 in blood. The experiment was performed in triplicate with 3 animals in each group. Error bars are SEM for n = 9. a R vs C of the respective tissue; b 24 h DR vs R of the respective tissue; c 72 h DR vs R of the respective tissue; d 5 th day DR vs R of the respective tissue. *P < 0.01, **P < 0.001, NS = not significant. GST activity in differentially treated mice. Mice were dissected at different time intervals. Experiments were performed in triplicate with 3 animals in each group. Tissues homogenates were prepared from excised lungs and liver. GST activity measured at 340 nm is expressed as mM GSH-CDNB conjugate formed/min/mg protein in tissues and mM GSH-CDNB conjugate formed/min/ml x 10 -2 in serum. Error bars are SEM for n = 9. a R vs C of the respective tissue; b 24 h DR vs R of the respective tissue; c 72 h DR vs R of the respective tissue; d 5 th day DR vs R of the respective tissue. *P < 0.01, **P < 0.001, NS = not ...

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... the unstressed and stressed neutrophils the values for superoxide radicals were 0.123 ± 0.009 and 1.623 ± 0.1, respectively, and the data obtained for stressed neutrophils was used as the 'control' for this study. With the increasing concentration of the cucurbits extracts (0.01, 0.02, 0.06 and 0.08 mg/ml) added to a well containing 250 µl of the neutrophils in HBSS, the SOD activity was enhanced and the superoxide radicals were appreciably scavenged and reduced. Addition of 0.08 mg/ml of each of the cucurbit extracts reduced the superoxide radicals as follows: Ls 40%, Cp 36% and Lc 31% (Fig.1). However, an increase in the concentration of cucurbit extract to the extent of 0.12 mg/ml did not increase the SOD further and rather decreased to some extent. The superoxide radicals therefore remained in more abundance at this concentration of cucurbit. Administration of indomethacin also followed the same pattern. An increase in the concentration of indomethacin from 0.01 to 0.08 mg/ml rendered progressive scavenging of superoxide radicals up to 44%. However, the presence of 0.12 mg/ml of indomethacin decreased SOD to some extent and therefore the decrease in scavenging of superoxide radicals was observed as 40% ...

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... depict lung tissue sections from control mice stained with DAPI showing nucleus and FITC indicating prominent localisation of EC-SOD in alveolar parenchyma and matrix, respectively. In radiation exposed group FITC staining, indicating the presence of EC-SOD, was found diminished in comparison to controls, indicating loss in radiation mediated EC-SOD expression (Fig.1D). G-002M pre- treatment could significantly retain EC-SOD expression both in extracellular spaces and cell lining of bronchioles, expressed with more prominent staining (Fig.1F). Lungs of G-002M group mice showed localization of EC-SOD comparable to controls (Fig.1H). DAPI in this study was used to confirm the existence of cells in all the experimental groups (Figs.1ACEG). Fig.2 indicates immunolabeling of EC-SOD in liver tissues. In control mice (Fig.2B), FITC staining in sinusoidal lining and vascular wall was quite visible indicating rich existence of EC-SOD in these areas. Radiation exposure in these animals has significantly descended the presence of EC-SOD which is indicated in the figure in the form of faintly stained sections (Fig.2D). In G-002M plus irridiated group, we could see enhanced intensity of the stain expressing increase in EC-SOD expression in comparison to radiation exposed group (Fig.2F). G-002M group animals showed intense staining of EC-SOD in liver sections which was comparable to controls (Fig.2H). Sections stained with DAPI (Figs.2ACEG) have confirmed the existence of nucleus in hepatocytes. Nucleus (DAPI) staining in different groups: (A) controls; (C) irradiated; (E) G-002M pre-treated ...

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... depict lung tissue sections from control mice stained with DAPI showing nucleus and FITC indicating prominent localisation of EC-SOD in alveolar parenchyma and matrix, respectively. In radiation exposed group FITC staining, indicating the presence of EC-SOD, was found diminished in comparison to controls, indicating loss in radiation mediated EC-SOD expression (Fig.1D). G-002M pre- treatment could significantly retain EC-SOD expression both in extracellular spaces and cell lining of bronchioles, expressed with more prominent staining (Fig.1F). Lungs of G-002M group mice showed localization of EC-SOD comparable to controls (Fig.1H). DAPI in this study was used to confirm the existence of cells in all the experimental groups (Figs.1ACEG). Fig.2 indicates immunolabeling of EC-SOD in liver tissues. In control mice (Fig.2B), FITC staining in sinusoidal lining and vascular wall was quite visible indicating rich existence of EC-SOD in these areas. Radiation exposure in these animals has significantly descended the presence of EC-SOD which is indicated in the figure in the form of faintly stained sections (Fig.2D). In G-002M plus irridiated group, we could see enhanced intensity of the stain expressing increase in EC-SOD expression in comparison to radiation exposed group (Fig.2F). G-002M group animals showed intense staining of EC-SOD in liver sections which was comparable to controls (Fig.2H). Sections stained with DAPI (Figs.2ACEG) have confirmed the existence of nucleus in hepatocytes. Nucleus (DAPI) staining in different groups: (A) controls; (C) irradiated; (E) G-002M pre-treated ...

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... depict lung tissue sections from control mice stained with DAPI showing nucleus and FITC indicating prominent localisation of EC-SOD in alveolar parenchyma and matrix, respectively. In radiation exposed group FITC staining, indicating the presence of EC-SOD, was found diminished in comparison to controls, indicating loss in radiation mediated EC-SOD expression (Fig.1D). G-002M pre- treatment could significantly retain EC-SOD expression both in extracellular spaces and cell lining of bronchioles, expressed with more prominent staining (Fig.1F). Lungs of G-002M group mice showed localization of EC-SOD comparable to controls (Fig.1H). DAPI in this study was used to confirm the existence of cells in all the experimental groups (Figs.1ACEG). Fig.2 indicates immunolabeling of EC-SOD in liver tissues. In control mice (Fig.2B), FITC staining in sinusoidal lining and vascular wall was quite visible indicating rich existence of EC-SOD in these areas. Radiation exposure in these animals has significantly descended the presence of EC-SOD which is indicated in the figure in the form of faintly stained sections (Fig.2D). In G-002M plus irridiated group, we could see enhanced intensity of the stain expressing increase in EC-SOD expression in comparison to radiation exposed group (Fig.2F). G-002M group animals showed intense staining of EC-SOD in liver sections which was comparable to controls (Fig.2H). Sections stained with DAPI (Figs.2ACEG) have confirmed the existence of nucleus in hepatocytes. Nucleus (DAPI) staining in different groups: (A) controls; (C) irradiated; (E) G-002M pre-treated ...

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... depict lung tissue sections from control mice stained with DAPI showing nucleus and FITC indicating prominent localisation of EC-SOD in alveolar parenchyma and matrix, respectively. In radiation exposed group FITC staining, indicating the presence of EC-SOD, was found diminished in comparison to controls, indicating loss in radiation mediated EC-SOD expression (Fig.1D). G-002M pre- treatment could significantly retain EC-SOD expression both in extracellular spaces and cell lining of bronchioles, expressed with more prominent staining (Fig.1F). Lungs of G-002M group mice showed localization of EC-SOD comparable to controls (Fig.1H). DAPI in this study was used to confirm the existence of cells in all the experimental groups (Figs.1ACEG). Fig.2 indicates immunolabeling of EC-SOD in liver tissues. In control mice (Fig.2B), FITC staining in sinusoidal lining and vascular wall was quite visible indicating rich existence of EC-SOD in these areas. Radiation exposure in these animals has significantly descended the presence of EC-SOD which is indicated in the figure in the form of faintly stained sections (Fig.2D). In G-002M plus irridiated group, we could see enhanced intensity of the stain expressing increase in EC-SOD expression in comparison to radiation exposed group (Fig.2F). G-002M group animals showed intense staining of EC-SOD in liver sections which was comparable to controls (Fig.2H). Sections stained with DAPI (Figs.2ACEG) have confirmed the existence of nucleus in hepatocytes. Nucleus (DAPI) staining in different groups: (A) controls; (C) irradiated; (E) G-002M pre-treated ...

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... black column represents the control group; for the other columns, the order is the same as in Fig.1.] Figure 3. Estimation of CAT activity generated in neutrophils due to the addition of stressors H2O2 or E.coli individually or their combination in equal quantity. Data from three independent experiments were averaged. The Ls, Cp and Lc were significantly effective in scavenging peroxide radicals than control (P < 0.05). [I, double control (un-stressed neutrophils); II, E.coli; III, H2O2; IV, H2 H2O2 + E.coli (control); V: H2O2 + E.coli + indomethacin; VI, H2O2 + E.coli + Cp; VII, H2O2 + E.coli + Lc; and VIII, H2O2 + E.coli + Ls] Fig.4 depicts the IC 50 values for various agents studied here. Indomethacin rendered IC 50 for COX-1 as 0.0154 mg/µl, followed by Cp (0.026 mg/µl), Lc (0.0337 mg/µl) and Ls (0.0335 mg/µl). Similarly, as to see in Fig.5, indomethacin revealed an IC 50 for COX-2 as 0.0427 mg/µl, followed by Cp (0.023 mg/µl), Lc (0.0183 mg/µl) and Ls (0.015 mg/µl). Statistical analysis revealed that the IC 50 of COX-1 by Ls, Lc and Cp were 2.17, 2.18 and 1.68 times less effective than indomethacin. However the IC 50 of COX-2 by Ls, Lc and Cp were 0.35, 0.428 and 0.53 times more effective than indomethacin (P < ...

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... this study, 36 components representing 96.8% of the W.saharae leaves oil were identified. The chemical composition of the essential oil was dominated highly by the oxygenated sesquiterpenes (44.3%) followed by oxygenated monoterpenes (40.0%). The most abundant compounds were β-eudesmol (24.6%), trans-nerolidol (18.2%) and linalool (16.8%). These three compounds represent 59.6% of the total oils (Fig.1). These results were in accordance with those previously reported in literature [8,9,10]. Indeed, Znini et al identified only 3 compounds such as eudesmol, linalool and nerolidol [9]. Thirty compounds amounting 91% of the oil, were identified by Essaqui et al [8]; the major components were β-eudesmol, trans-nerolidol and linalool [10]. Among the other chemical components were linalool, 1,8-cineole, camphor, p-cymene, terpinen-4-ol and sabinene. The differences recorded for the chemical composition of the essential oil of W.saharae can be according to the genetic characteristics and climatic, seasonal, geographical and geological differences where the plant is collected. Among identified compound, nerolidol showed anti- leishmanial activity [18] and exhibits antineoplastic activity [19]. This compound is a sesquiterpene present in essential oils of several plants, approved by the US Food and Drug Administration (FDA) as a food flavoring agent. Beta-eudesmol has multiple pharmacological effects; the anti-inflammatory effect of β-eudesmol was shown recently [20]. ...

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... lungs, EC-SOD, the key antioxidant enzyme, is well reported to prevent free radicals mediated tissue damage [4,7,8]. Since lungs have large quantity of connective tissues and vessels, the enzyme EC-SOD is highly expressed as compared to the other tissues. This enzyme contains a heparin or matrix binding domain, which enables it to bind to the matrix and to cell surfaces in tissue. This matrix-binding domain is sensitive to proteolysis [35]. In the current study, whole body exposure to lethal dose of gamma radiation to mice has resulted in significant loss of EC-SOD from extracellular matrix of the lung (Figs.1D&3A). This indicates that radiation has either triggered the release of some proteases in extracellular matrix which catalyze the proteolysis of heparin binding domain or over-utilized this enzyme during superoxide radical scavenging process. Protection against functional and tissue damage in the lungs has been demonstrated earlier also by administration of manganese (Mn)SOD and SOD mimetic [9]. In consonance, present study confirms protection delivered to the lung tissues of lethally irradiated mice by pre-administration of G-002M. Observations demonstrate that this protection could have been due to G-002M mediated enhanced expression of EC-SOD (Figs.1F&3A) along with the up-regulation of other endogenous antioxidant enzymes in blood and lung tissues (Figs.7,8,10,11). Current study also is in corroboration to the previous findings where EC-SOD has been shown to extend protection to the lung inflammation and fibrosis induced by oxidative stress ...

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... lungs, EC-SOD, the key antioxidant enzyme, is well reported to prevent free radicals mediated tissue damage [4,7,8]. Since lungs have large quantity of connective tissues and vessels, the enzyme EC-SOD is highly expressed as compared to the other tissues. This enzyme contains a heparin or matrix binding domain, which enables it to bind to the matrix and to cell surfaces in tissue. This matrix-binding domain is sensitive to proteolysis [35]. In the current study, whole body exposure to lethal dose of gamma radiation to mice has resulted in significant loss of EC-SOD from extracellular matrix of the lung (Figs.1D&3A). This indicates that radiation has either triggered the release of some proteases in extracellular matrix which catalyze the proteolysis of heparin binding domain or over-utilized this enzyme during superoxide radical scavenging process. Protection against functional and tissue damage in the lungs has been demonstrated earlier also by administration of manganese (Mn)SOD and SOD mimetic [9]. In consonance, present study confirms protection delivered to the lung tissues of lethally irradiated mice by pre-administration of G-002M. Observations demonstrate that this protection could have been due to G-002M mediated enhanced expression of EC-SOD (Figs.1F&3A) along with the up-regulation of other endogenous antioxidant enzymes in blood and lung tissues (Figs.7,8,10,11). Current study also is in corroboration to the previous findings where EC-SOD has been shown to extend protection to the lung inflammation and fibrosis induced by oxidative stress ...

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... chemical composition of green propolis was evaluated by HPLC analysis (Fig.1), showing high levels of phenolic compounds. The total content of phenolic compounds is 151.69 mg/g of dried ...