الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Mushrooms have been used not only as a source of food but a medicinal resource. There are at least 200 species of mushrooms have been used for various traditional medical purposes. The most cultivated mushroom worldwide is Agaricus bisporus (button mushroom), followed by Pleurotus spp (oyster mushrooms). Mushrooms have been shown to stimulate the immune system, They have been proven to also have cholesterol-lowering, anti-inflammatory, antimicrobial, antioxidant, anti-mutagenic, anti-tumor as well as properties that help reduce the risk of heart disease, assist in the treatment of AIDS, herpes and other viral conditions, help treat Hepatitis, treatment of Chronic Fatigue Syndrome, Influenza, Tuberculosis, staphylococcus sepsis, leprosy, environmental allergies, Bronchial Inflammation, Hodgkin’s disease and stomach ulcers. With little scientific evidence, many investigators have endeavored to study the hypoglycemic effect from either the fruiting body or mycelia of various edible/medicinal mushrooms.
Diabetes mellitus (DM) is a common irreversible metabolic disorder. Currently there is not a perfect approach to treat diabetes and its complications, due to variability in the causes of diabetes. Animal models provide a useful tool for the screening of drugs for the prevention and treatment of diabetes.
This gives me the impetus to study the effect of mushroom on the expression some genes that play a pivotal role in glucose homeostasis in diabetic mice. A trail to find a possible explanation for their hypoglycemic properties.
In the following study we used diabetic animal model to evaluate the possible hypoglycemic effect of two different types of edible mushrooms that cultivated and produced in Egypt on the glycemic state in STZ- diabetic induced mice.
Fifty-six male Swiss mice of average age 4-5 months and weight at the beginning of the experiment 25±3 grams, were housed in groups of seven in stainless steel cages in a room with controlled temperature (22°C ± 2°C), a relative humidity of 55% ± 5%, with a light-dark phase of 12 hours each, with free access to basal diets and water. There are no restrictions in Egypt for the use of experimental animals for laboratory studies.
After acclimatization for 7 to 10 days, fourteen mice served as control group (group-A) and they are fed on base diet. The remaining mice were fasted for 12 hours before Intra-peritoneal administration of single dose of STZ at 100 mg/kg body weight. Two days after STZ treatment, the rats were considered diabetic (diabetic group-B), as determined by non-fasting blood glucose levels of >200 mg/dL. The diabetic group were sub-classified into 2 groups; sub-group B1(n=14): which treated by insulin (0.3 units/ 50 gm body weight dissolved in 0.5 ml physiological saline, sub-group B2 (n=14) :which fed on oyster mushroom (Pleurotus ostreatus); sub-group B3(n=14): which fed on Agaricus mushroom (Agaricus bisporus). Both groups were subdivided into two sub-groups a, b : sub-group a scarified after 4 weeks, sub-group b sacrificed after 8 weeks , the animals were fasted for 12 hours before scarification after the final oral dosing. The fresh fruiting bodies of P ostreatus and A bisporus were incorporated into the diet by dose of (62•5 g/kg). Body weight and blood glucose have been taken every week.
Blood samples were collected after 4 and 8 weeks for determination of serum insulin level. Tissue samples were taken from liver for biochemical determination of GK activity and hepatic glycgogen contents. Samples for Molecular investigations were taken from liver, pancreas and adipose tissue for determination of mRNA expression level of SIRT, GK, IRA, GLUT2, Insulin, GLUT4 and PPAR-ɣ respectively, Using RT-PCR.
Our results after they were statistically analyzed revealed the following:
• Body weight
There was a steady increase in average body weight (gm) over the course of the study. The increases in body weight show insignificant difference between the STZ-induced diabetic mice fed on mushrooms and insulin.
• Fasting blood glucose level
The blood glucose was significantly lowered in mushrooms feeding diabetic groups and insulin treated ones compared to their control group.
• Hepatic GK activity
There is an observed variation in the activity of the enzyme in all groups at the first part of the experiment. In the second part of the experiment the GK activity was significantly increased in all diabetic treated groups.
• Hepatic glycogen content
Hepatic glycogen contents show variation among groups in the two durations of the experiment. There was an oscillation in the first duration of the experiment while it was significantly increased in diabetic treated groups in the second duration if compared with their control.
• Serum insulin level
Serum insulin level was significantly increased in mushrooms feeding groups and insulin treated one compared to the control group although there is no significant increase in the first duration, it significantly increased in the mushroom fed group and insulin treated one in second duration if compared with their control.
• mRNA expression of silent information regulatory protein 1 (SIRT1) in hepatic tissues
The expressional level of mRNA of SIRT1 was increased in diabetic treated groups with mushrooms and insulin if compared with their control group in the same duration.
• mRNA expression of Glucokinase (GK) in hepatic tissues
The expressional level of mRNA of GK was increased in diabetic treated groups with mushrooms and insulin if compared with their control group in the same duration.
• mRNA expression of Insulin in pancreatic tissues
The expressional level of mRNA of Insulin was increased in diabetic treated groups with mushrooms and insulin if compared with their control group in the same duration.
• mRNA expression of insulin receptor A (IRA) in hepatic tissues
The expressional level of mRNA of IRA was increased in diabetic treated groups with mushrooms and insulin if compared with their control group in the same duration.
• mRNA expression of Glucose transporter 2 (GLUT2) in hepatic tissues
The expressional level of mRNA of GLUT2 was increased in diabetic treated groups with mushrooms and insulin if compared with their control group in the same duration.
• mRNA expression of glucose transporter 4 (GLUT4) in adipose tissues
The expressional level of mRNA of GLUT4 was increased in diabetic treated groups with mushrooms and insulin if compared with their control group in the same duration.
• mRNA expression of proxisome proliferating activator receptor gamma (PPAR-γ) in adipose tissues
The expression level of mRNA of PPAR-γ was increased in diabetic treated groups with mushrooms and insulin if compared with their control group in the same duration.