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العنوان
The Possible Protective Role of Resveratrol against Zinc Oxide Nanoparticles Induced Hepatic Tissue Injury in Adult Albino Rat \
المؤلف
Mohamed, Thoria Abd-El hamed Yousef.
هيئة الاعداد
باحث / ثريا عبد الحميد يوسف محمد
مشرف / حسين محمد ابراهيم
مشرف / ولاء عاطف الفخرانى
مشرف / شيماء مجدى محمد
تاريخ النشر
2022.
عدد الصفحات
147 p. :
اللغة
الإنجليزية
الدرجة
ماجستير
التخصص
تشريح
تاريخ الإجازة
1/1/2022
مكان الإجازة
جامعة عين شمس - كلية الطب - علم التشريح والأجنة
الفهرس
Only 14 pages are availabe for public view

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Abstract

Nanotechnology is a rapidly growing field that has been used in a wide range of applications, including engineering, agriculture, and medicine. ZnO NPs are commonly used in many industries and medications, which lead to an increased risk of exposure to their harmful side effects.
The liver is considered the target organ for toxic substances. It has a key role in the metabolism of chemicals and drugs. So, ZnO NPs accumulate in the liver more than in the rest of the organs.
The aim of this work was to study the effect of ZnO NPs on the histological structure of the liver of adult male albino rats and to evaluate the possible protective role of Resveratrol.
Forty adult male albino rats (3-6) months old (weighing 150-200 grams) were used in this study. The animals were divided into four groups with ten rats each.
• group I: (control group) in which rats received basal standard feed and fresh water only, without any intervention for four weeks.
• group II: (ZnO NPs group) rats were treated with zinc oxide nanoparticles (50 mg /kg B.W. /day) for four weeks via oral gavage.
• group III: (Resveratrol group) rats were treated with Resveratrol (20 mg/kg B.W. /day) for four weeks via oral gavage.
• group IV: (ZnO NPs + Resveratrol group) rats were co-treated by a combination of zinc oxide nanoparticles and Resveratrol with the same doses and the same route as in groups II and III for four weeks, respectively.
At the end of the experiment, blood samples were collected for ALT, AST, and ALP measurements. Then animals were sacrificed to collect liver specimens from all groups, which were dissected and processed to be examined by light microscope.
Examination of groups I and III (Control and Resveratrol groups) showed the liver tissue was formed of the classic hepatic lobules. Each lobule consisted of plates of hepatocytes arranged radially around a central vein to the periphery of the lobule where the portal tracts were located. The irregular spaces between the hepatic plates were occupied by liver sinusoids. The hepatocytes appeared polygonal in shape, with acidophilic cytoplasm and rounded basophilic nuclei.
Liver sections stained with Masson’s trichrome stain in groups I and III showed few collagen fibers around the central veins, in between the hepatic cords and the sinusoids and also around the portal tracts. Moreover, liver sections stained with Periodic acid-Schiff showed a strong positive PAS reaction within the cytoplasm of the hepatocytes of group I, while it showed a highly strong positive PAS reaction in group III. Immunohistochemical stain showed a negative immune reaction to Caspase-3 inside the cytoplasm of hepatocytes in both groups.
On the other hand, the liver sections obtained from group II (ZnO NPs group) revealed that the hepatic architecture was disorganized. The central veins were dilated, congested, and contained areas of detached endothelial lining. The blood sinusoids were congested, dilated, and irregular with lymphocytic infiltration.
The hepatocytes displayed obvious variable degrees of cellular damage. Some hepatocytes appeared necrotic with deeply stained acidophilic cytoplasm and darkly stained nuclei, and some hepatocytes showed signs of hydropic degeneration in the form of finely granular cytoplasm with variable-sized vacuolations. The hepatic parenchyma showed an apparent increase in cellular apoptosis. Some hepatocytes lost their cell boundaries and coalesced together. The number of binucleated cells was also increased. However, apparently some normal hepatocytes with vesicular nuclei were still seen in between the damaged cells. The portal tracts showed vascular congestion, dilatation with the proliferation of the bile ductules and marked inflammatory cell infiltration.
Moreover, liver sections stained by Masson’s trichrome stain demonstrated that there was an obvious increase in collagen deposition around the portal tracts, central veins, and in between the hepatic cords and the sinusoids. Liver sections stained with PAS showed diffuse hepatic glycogen depletion and most of the hepatocytes revealed a negative PAS reaction. Only a few hepatocytes showed a mild PAS reaction. Immunohistochemical examination showed that most of the hepatocytes had a strong positive reaction to Caspase-3 immuno-stain.
When compared to the control group, the ZnO NPs treated group had a statistically significant increase in the area percentage of collagen fibers deposition, the area percentage of Caspase-3 expression, and a statistically significant decrease in the optic density of PAS stain.
The liver sections obtained from group IV (the ZnO NPs and Resveratrol treated group together) demonstrated restoration of the liver architecture with few areas of subcapsular haemorrhage. The hepatocytes were arranged as regularly radiating liver cords around the central veins.
Most of hepatocytes appeared polygonal in shape, with acidophilic cytoplasm and central rounded vesicular nuclei, while few hepatocytes appeared degenerated with dark stained nuclei and cytoplasm showing hydropic degeneration. Furthermore, the blood sinusoids returned to their normal size, however, they were sometimes congested and dilated. Also, the portal tracts returned to their normal sizes with a marked decrease in inflammatory cell infiltration.
In our study, liver sections stained by Masson’s trichrome stain in group IV showed a marked decrease in collagen fibers deposition, especially around the portal tracts, and in between hepatocytes. This is matched with histomorphometric analysis results which revealed a highly statistically significant decrease in the area percentage of collagen deposition, in group IV compared to group II.
Another finding in the present work, in group IV, was that Resveratrol restored the glycogen content of hepatocytes which was depleted in group II. This was marked by a strong PAS positive reaction in the cytoplasm of most hepatocytes. Also this was confirmed by the histomorphometric study which revealed that group IV had a highly significant increase in the optic density of PAS stain in the hepatocytes as compared to group II.
Resveratrol co treatment with ZnO NPs significantly reduced the apoptosis of hepatocytes. This was evident in our study by an apparent negative Caspase-3 reaction in the cytoplasm of most of hepatocytes and by histomorphometric analysis; there was a statistically significant decrease in the area percentage of Caspase-3 expression in group IV compared to ZnO NPs treated group.
Clear deterioration of liver function tests was observed in ZnO NPs group compared with the control, with marked improvement in the group treated with ZnO NPs and Resveratrol together.