الفهرس 
Chapter I : Introduction & Aim of the workOnly 14 pages are availabe for public view
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Abstract
Diabetes Mellitus (DM) is a heterogeneous metabolic disorder characterized by hyperglycemia resulting from defective insulin secretion, resistance to insulin action or both. In diabetes mellitus, oxidative stress seems mainly to be due to an increased production of free radicals and/or a sharp reduction of antioxidant defenses. Oxygen-derived free radicals have been implicated in the pathophysiology of various disease states; including diabetes mellitus Oxidative stress has been suggested to be involved in the pathogenesis. The complications related to DM may result from hyperglycemia and the generation of free radicals, which damage cellular components such as lipids, proteins, and DNA. Clinical and experimental findings suggest that the liver, similarly to other organs, may also be affected by DM in the long-term.
Thymoquinone (TQ) is a bioactive compound obtained from volatile oil of Nigella sativa. TQ has been reported to exhibit many pharmacological effects, including immunomodulatory, anticancer, anti-diabetic, antioxidant, and anti-inflammatory activities.
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TQ regulates serum concentrations of cholesterol, triglycerides and glucose. It can be beneficial in preventing and treating hyperglycemia and dyslipidemias.
The present study aimed to declare possible effect of thymoquinone to manage diabetes mellitus and preventing associated abnormalities. To test that, we will investigate the effect of TQ on fasting blood sugar, cholesterol , triglycerides, AST,ALP, lipid peroxidation, total anti-oxidant capacity , insulin receptor and glucose transporter-2 (Glut-2) gene expression in liver of streptozotocin (STZ) induced DM in male rats.
Diabetes mellitus was induced in rats by single intraperitoneally injection of 65 mg/kg body weight of STZ .
Rats were classified into the following 5 groups, each group contained 10 rats:
group 1: (G1) Control .
group 2: (G2) Diabetes Mellitus
group 3: (G3) Diabetes Mellitus treated with TQ
Treated with 80 mg/kg /day of TQ for 6 weeks.
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group 4: (G4) Diabetes Mellitus treated with MET
Treated with 500 mg/kg /day of MET for 6 weeks
group 5: (G5) Diabetes Mellitus treated with TQ + MET
Treated with 80 mg/kg/day of TQ and 500 mg/kg of MET daily for 6 weeks.
At the end of experiment, rats were anesthetized with ether; tissues and blood will be collected for estimation of these parameters:
1.Biochemical investigations as serum glucose concentration, ALT, ALP, cholesterol triglycerides, MDA and TAC.
2.Relative expression of Glut2 gene in liver tissue.
3. Histological investigation for liver and pancreatic tissues.
4.Immunohistochemical investigation for insulin receptor in liver tissue .
The results of this study revealed the followings:
Body weight, relative expression of Glut2 gene insulin receptors levels and liver and pancreatic TAC were showed a significant decreased in DM group as compared with control group.
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Moreover TQ or MET or together improve these parameter but the maximum effect of combine treatment was noticed.
In addition fluid intake, fasting blood glucose, cholesterol, triglycerides and liver and pancreatic MDA were showed a significant increase in DM group as compared with control group. Moreover TQ or MET or together reduce this levels with different grades.
Histological investigation supports our results as the effect of diabetes was noticed and also the effect of treatment by TQ or MET or together was noticed on liver sections of different groups.