الفهرس 
Gross Anatomy Of The Human LiverOnly 14 pages are availabe for public view
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Abstract
Introduction: Liver fibrosis is a common consequence of chronic liver diseases, Liver transplantation has been the only available treatment option for patients diagnosed with the end-stage liver fibrosis or cirrhosis. However, a number of disadvantages, including a high cost and transplant rejection following liver transplantation, have largely limited its clinical application. Therefore, novel therapeutic approaches are required for the treatment of liver fibrosis and to improve care for such patients Recently, stem cell-based therapy and simvastatin have shown promising benefit on animal models and some clinical patients.
The aim of the work was to study the effect of carbon tetrachloride on the rat liver, evaluate the rule of bone marrow mesenchymal stem cells, simvastatin in self renewal and tissue regeneration and the effect of combination of bone marrow mesenchymal stem cells and simvastatin in treatment of hepatic damage.
Materials and Methods: this study was carried out on 60 male albino rats, 6 rats were used for preparation of bone marrow mesenchymal stem cells. then 54 rats were divided into 6 groups, group I (control group): 18 rats divided into (negative control group): 9 rats chosen randomly as negative control group (normal healthy rats), not received any drugs, (positive control group) subdivided into three subgroups, 3 rats each, group a injected with 1ml/kg olive oil (solvent of CCL4) intraperitoneally twice weekly for six weeks, group b injected with 0.5 % solution of xanthan gum (solvent of simvastatin) intraperitoneally twice weekly for six weeks and group c injected with 1.5 ml of phosphate buffered saline ( solvent of stem cells) intraperitoneally twice weekly for six weeks, group II (carbon tetrachloride group): 9 rats injected with 1 ml/kg body weight CCl4 dissolved in 1 mg of olive oil intraperitoneally twice a week for 6 weeks, group III (CCL4 – BM-MSCs): 9 rats injected with carbon tetrachloride as group 3. After 6 weeks, these rats were injected with single dose of BM-MSCs intravenous through the tail vein at a dose 3*10⁶ cells/ml in a volume of 1.5 ml PBS for 8 weeks, group IV (CCL4 – simvastatin): 9 rats injected with carbon tetrachloride as group 3. then an oral daily dose of 10 mg Simvastatin/kg body weight suspended in 0.5 % solution of xanthan gum for 8 weeks and group V (CCL4-MSC/Simvastatin): 9 rats injected carbon tetrachloride as group 3. Then received a combination treatment of both MSCs and Simvastatin in the same regimen mentioned previously above.
At the end of the experiment, the rats of the studied group were anaesthetized by ether inhalation. The blood samples were collected from the tail vein and centrifuged at 3,000 rpm for 15 min to separate serum, which was used to measure the activities of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP), and the level of albumin.
The liver was rapidly removed by dissection, washed by ice-cold physiological saline and dried. For histopathological study, specimens of the liver tissues were fixed in 10 % formalin and embedded in paraffin wax. Three sections (4 µm thick) were prepared for histopathological examination Hematoxylin and eosin stain, Masson’s trichrome stain, Transforming growth factor-beta 1 and Immunohistochemical stain (CD 105).
Statistical analysis: Data were expressed as mean ± SD. Significant difference was determined for all groups.
Results: The present work demonstrated that Haematoxylin and eosin-stained sections of control rat livers showed normal morphology. Normal polygonal classic hepatic lobules, each hepatic lobule formed of cords of hepatocytes radiating from central veins towards the periphery of the lobules. Hepatic cells contain vesicular nucleus and acidophilic cytoplasm. Few hepatocytes were binucleated. Distinct flat endothelial lining of central vein and sinusoidal spaces. The portal areas at the corners of these lobules, composed of branches of normal hepatic artery, portal vein and bile duct.
In the CCL4 treated group, histopathological changes appeared as distortion of Hepatic lobular architecture; Dilated congested central vein, multiple ballooned hepatocytes with dark nuclei and a vacuolated cytoplasm appeared around dilated central veins. Some hepatocytes with deeply acidophilic cytoplasm and shrunken deeply stained nuclei were noticed. Fatty infiltration among hepatocytes was observed. In addition, inflammatory cellular infiltration was seen between degenerated hepatocytes. Portal area with dilated congested portal vein with detached endothelial lining and bile duct proliferation.
The CCL4/BM-MSCs treated rats showed partial improvement in the hepatic lobular architecture. Hepatocytes appeared nearly similar to that of the control group with normal sinusoids, some cells were vacuolated, others with deep acidophilic cytoplasm and some cells were binucleated. Flat endothelial lining the central vein and hepatic sinusoids. The portal area showed dilated congested portal vein with normal endothelium, normal hepatic artery and bile duct. fatty infiltration and cellular infiltration were evident.
The CCL4/Simvastatin treated group also showed mild congestion of central vein, dilated blood sinusoids in between hepatocyte cords with detached areas of its endothelium. Most hepatocytes were with dark nucleus and vacuolated cytoplasm, others with deep acidophilic cytoplasm. The portal area with dilated congested portal vein, normal hepatic artery and bile duct. Fatty infiltration and cellular infiltration were evident.
The CCL4/BM-MSCs/Simvastatin treated group showed hepatic tissues appeared to have nearly normal architecture.
The present study demonstrated that Masson trichrome stained sections of control rat livers showed normal morphology, few collagen fibers were well seen surrounding the central veins and the structures in the portal areas.
The CCL4 treated group showed increase in collagen fibers around the central veins and surrounding the structure of the portal area.
The CCL4/BM-MSCs treated group showed minimal collagen proliferation recorded at the portal areas and around the central veins.
The CCL4/Simvastatin treated group showed minimal to moderate amount of collagen fibers around central veins and portal areas.
The CCL4/BM-MSCs/ Simvastatin treated group showed few amount of collagen fibers surrounding central veins and portal areas.
Transforming growth factor stained sections of control rat livers showed weak positive immune-reaction represented as brown cytoblasmic granules in the wall of the central vein and in between the hepatocytes.
The CCL4 treated group showed strong positive immune-reaction represented as brown cytoblasmic granules in the wall of the central vein and in-between the hepatocytes.
The CCL4/BM-MSCs treated group showed mild expression of immune-reaction in the wall of the central vein and in between the hepatocytes.
The CCL4/Simvastatin treated group showed moderate expression of immune-reaction in the wall of the central vein and in between the hepatocytes.
The CCL4/BM-MSCs/ Simvastatin treated group showed minimal expression of immune-reaction in the wall of the central vein and in between the hepatocytes.
BM-MSCs treated hepatic tissue had shown positive cell membranous reaction for CD105 in the form of brown pigmentation of cell membrane and cytoplasm of hepatic cells which means that transplanted BM -MSCs had differentiated into these hepatic cells as CD105 characterizes MSCs.
These findings were supported by morphometric results and statistical analysis which showed that the serum liver functions tests of rats of CCL4 group showed a significant increase in serum activities of ALT, AST, and ALP when compared with the control group. While the serum albumin was significantly decreased when compared with the control group. With the MSCs, Simvastatin and combined therapy, there was a significant decrease in the level of serum ALT, ALP and AST activities in comparison with the CCL4 group. While the serum albumin was significantly elevated when compared with the CCl4 group.