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العنوان
THE POSSIBLE PROTECTIVE ROLE OF PLANT POLYPHENOLS AGAINST THE GENOTOXICITY OF ACROLEIN ON BONE MARROW chrOMOSOMES AND DNA IN MALE ALBINO MICE /
المؤلف
El-Ashry, Sally Ramadan Gabr Eid.
هيئة الاعداد
باحث / سالى رمضان جبر عيد العشرى
مشرف / نجلاء زكي إبراهيم الألفي
مشرف / محمود فتحي محمود
تاريخ النشر
2021.
عدد الصفحات
507 P. :
اللغة
الإنجليزية
الدرجة
الدكتوراه
التخصص
علم الحيوان والطب البيطري
تاريخ الإجازة
1/1/2021
مكان الإجازة
جامعة عين شمس - كلية التربية - قسم العلوم البيولوجية والجيولوجية
الفهرس
Only 14 pages are availabe for public view

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from 507

Abstract

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Natural polyphenolic substances exist in several foods and drinks of plant origin such as fruits, vegetables, tea and coffee, protect against the oxidative stress of reactive oxygen species and promote human health. Acrolein is a reactive α, ß-unsaturated aldehyde, causes cytotoxicity, genotoxicity and mutagenic effects. The present work is mainly concerned with the study of the protective effect of two plant polyphenols, quercetin and/or resveratrol, against the cytotoxicity, clastogenicity and genotoxicity of acrolein on bone marrow chromosomes and DNA content of male albino mice (Mus musculus).
One hundred mice (CD-1) were acclimated for one week and randomly assigned to one of ten groups, comprising of ten animals each as follows: group 1: mice served as a control group and received distilled water (the acrolein’s solvent) orally at same volume as acrolein treatment. group 2: mice served as quercetin-vehicle control group and received corn oil (the quercetin’s vehicle) orally at same volume as quercetin for eight consecutive days. group 3: mice served as resveratrol-vehicle control group and received 2% ethyl alcohol (the resveratrol’s vehicle) orally at same volume as resveratrol for eight consecutive days. group 4: mice received oral dose of acrolein (10 mg/kg b. wt.) for four consecutive days. group 5: mice received oral dose of quercetin (50 mg/kg b. wt.) for eight consecutive days. group 6: mice received oral dose of quercetin (50 mg/kg b. wt.) alone for four consecutive days directly prior to oral treatment with both quercetin (50 mg/kg b. wt.) followed by acrolein (10 mg/kg b. wt.) for other four consecutive days. group 7: mice received oral dose of resveratrol (12.5 mg/kg b. wt.) for eight consecutive days. group 8: mice received oral pretreatment with resveratrol (12.5 mg/kg b. wt.) alone for four consecutive days directly prior to oral treatment with both resveratrol (12.5 mg/kg b. wt.) followed by acrolein (10 mg/kg b. wt.) for other four consecutive days. group 9: mice received both quercetin (50 mg/kg b. wt., orally) and resveratrol (12.5 mg/kg b. wt., orally) for eight consecutive days. group 10: mice received oral pretreatment with quercetin and resveratrol (50 mg/ kg, 12.5 mg/kg b. wt., respectively) for four consecutive days directly prior to oral treatment with both quercetin and resveratrol followed by acrolein (10 mg/ kg b. wt.) for other four consecutive days. All the control and treated animals were sacrificed by cervical dislocation at 24 hr after the last treatment for collection of samples.
Results of bone marrow chromosomes analysis revealed that there were 40 telocentric chromosomes in the normal bone marrow cells of male albino mice. They were divided into five distinct groups; each had the chromosomes of nearly equal lengths.
The present study revealed that acrolein (10 mg/kg b. wt.) administration for four consecutive days significantly (p < 0.001) increased the incidence of structural and numerical chromosomal aberrations in the bone marrow cells of male mice in comparison to the corresponding control group. However, the mean of centromeric attenuation, fragment, deletion and sticky chromosomes were higher as compared to other chromosomal aberrations.
In contrast, oral pretreatment of plant polyphenols (quercetin and/or resveratrol) prior to acrolein treatment significantly (p < 0.001) decreased the mean of total aberrations comparable to that of acrolein-administrated group. In addition, this study observed that pretreatment with quercetin prior to acrolein treatment gave more effective reduction in the frequency of total chromosomal aberrations than pretreatment with resveratrol or pretreatment with both quercetin and resveratrol.
In the present study, a highly significant (p < 0.001) reduction in the percentage of mitotic index of bone marrow cells was observed in the acrolein-administrated group compared to the corresponding control group. In addition, it was observed that the two plant polyphenols (quercetin and/or resveratrol) repaired the decrease in the percentage of mitotic index which caused by acrolein administration.
Current results of bone marrow chromosomal C-banding and G-banding analysis showed that all bone marrow chromosomes of the control male albino mice were found to have C-bands at or close to their centromeric regions except the Y chromosome which appeared without C-bands. Additionally, they showed that all bone marrow chromosomes of the control male albino mice were clearly observed with G-band patterns of different thickness, degree of staining and number of G-bands.
Also, resuls of C-banding and G-banding analysis confirmed the protective effect of quercetin and/or resveratrol against acrolein-induced clastogenesis in bone marrow cells of male albino mice by decreasing the frequency of structural and numerical chromosomal aberrations resulted from acrolein administration.
The present results of sister chromatid exchange (SCE) analysis showed that the frequency of sister chromatid exchanges was significantly (p < 0.05) increased in the acrolein-treated group when compared with the corresponding control group. However, the oral pretreatment with quercetin and/or resveratrol prior to acrolein administration significantly (p < 0.05) reduced the incidence of SCEs in comparison with that after oral administration with acrolein alone which confirmed the protective effects of quercetin and/ or resveratrol against the clastogenic effect of acrolein in bone marrow cells of male albino mice.
Results of micronucleus assay showed that the frequency of micronucleated polychromatic erythrocytes (MNPCEs) was significantly (p < 0.05) increased in mice bone marrow cells of the acrolein treated group when compared to the corresponding control group. In contrast, the oral pretreatment with quercetin and/or resveratrol prior to acrolein administration significantly (p < 0.05) reduced the frequency of micronucleated polychromatic erythrocytes (MNPCEs) compared to MNPCEs frequency after oral administration with acrolein alone which confirmed the protective effects of quercetin and/or resveratrol against the cytotoxicity of acrolein in mice bone marrow cells.
The present results of cytotoxicity test showed a highly significant (p < 0.001) increase in cytotoxicity (PCEs/NCEs ratio) of the bone marrow cells of male albino mice as a consequence of acrolein treatment for four consecutive days in comparison to that of the control group. On the other hand, the anticytotoxic potential of quercetin and/or resveratrol caused a significant reduction in the cytotoxicity (PCEs/NCEs ratio) of bone marrow cells when compared to acrolein-treated group (group 4).
Results of comet assay revealed that the oral administration of acrolein significantly (p < 0.05) increased the comet parameters and the genotoxicity of liver cells of treated mice when compared to the corresponding control group. On the contrary, the antigenotoxic potential of quercetin and/or resveratrol caused a significant reduction in the comet parameters and the genotoxicity of liver cells of male albino mice when compared to acrolein-treated group.
In the present study, the expression levels of two genes coding for antioxidant enzymes; glutathione peroxidase 1 (GPx1) and superoxide dismutases 1 (SOD1) in mice liver tissues of the control and all treated groups were determined by quantitative real time-PCR (qRT-PCR). Results showed the expressional suppression of genes for antioxidative enzymes (GPx1 and SOD1) in liver cells of acrolein-administrated mice which indicated the oxidative stress and genotoxicity of acrolein, but it confirmed the expressional induction of these genes as a result of pretreatment of quercetin and/or resveratrol before acrolein administration which indicated the antioxidative activity of quercetin and/or resveratrol against acrolein toxicity.
In conclusion, the present investigation confirmed that acrolein, a toxic cyclophosphamide metabolite and a major component in the gas phase of cigarette smoking, automobile exhaust, overheated oils, fried foods and forest fires, was highly clastogenic, cytotoxic and genotoxic agent as it induced a very harmful genetic damage in the treated male albino mice (Mus musculus). Therefore, acrolein exposure should be limited by regulating its levels in foods and in tobacco products or preventing its huge emissions into environment. In addition, the observed protective effects of the two plant polyphenols, quercetin and/or resveratrol, indicated that they can be used as nutritional supplements or as a part of functional foods for geno protective treatment against acrolein induced genotoxicity in vivo. Onions, apples, grapes, berries, broccoli, citrus fruits, cherries, green tea and coffee are good sources of quercetin. Additionally, common dietary sources of resveratrol include grapes, mulberries, blueberries, peanuts, strawberries, cocoa powder, dark chocolate and soy.