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Abstract The heart is a muscular organ in humans and other animals, which pumps blood through the blood vessels of the circulatory system. Blood provides the body with oxygen and nutrients, as well as assists in the removal of metabolic wastes. Heart diseases have risen steadily over the last century, especially in industrialized countries, due to changes in diet, lifestyle and abuse of many drugs. Cardiovascular diseases are the most common cause of death globally as of 2008, accounting for 30% of death. Anabolic androgenic steroids are synthetic derivatives of testosterone and they are structurally related and have similar effects in the body as testosterone. Nandrolone decanoate (19-nortestosterone) is one of the most popular AAS among athletes because of its anabolic effect. Vitamin E refers to a group of compounds that include both tocopherols and tocotrienols. Clinically, vitamin E is used to prevent and repair cell and tissue damage during the radiation therapy. Alpha tocopherol is an important lipid –soluble antioxidant. As it is fat –soluble, it is incorporated into the cell membrane, which protects it from oxidative damage. Vitamin E performs its function as antioxidant in the glutathione peroxidase pathway. It protects the cells from oxidation by reacting with lipid radicals produced in the lipid peroxidation chain reaction. So vitamin E removes the free radical intermediates and prevent the oxidation reaction from continuing. This work was designed to focus on the histological and histochemical changes induced by nandrolone on the cardiac muscle of adult male albino rats and to clarify the possible protective effect of vitamin E. Material and Methods Fifty adult male albino rats weighing about 175- 225 gm were used in our study. The animals were randomly divided into four groups as follows: •group I (control group): included 10 animals, half of them received no treatment (IA) while the other half received corn oil daily orally (IB). •group II (vitamin E treated group): Included 10 animals which receive vitamin E at a dose of 400mg/kg/day orally by modified plastic syringe for four weeks. •group III (Nandrolone – Treated group): Included 20 rats to which nandrolone was given by intra-muscular injection at a dose of 10 mg/kg/week for four weeks. Half of rats were sacrificed 24 hour after the last injection (Subgroup IIIA). While the other half were left for two weeks after arrest of nandrolone treatment then sacrificed (Subgroup IIIB). •group IV (Nandrolone and Vitamin E-treated group): Composed of 10 rats, each was given nandrolone and vitamin E simultaneously at a dose similar to the previous groups. At the end of each detected period, the animals were anaesthetized then sacrificed. The thoracic cavity was opened, exposing the heart, which was then excised. Half of the cardiac muscles were fixed in 10% formal saline and paraffin sections were prepared and stained by (Haematoxylin and eosin stain, Masson’s trichrome stain and Periodic Acid Schiff’s reaction) for light microscopic study (L/M) and the other half were fixed in 1% glutaraldehyde in phosphate buffer for Electron Microscopic Study (E/M). Results and Conclusion: The following data have been observed in the present study: General appearance of animals: All animals of the control group and vitamin E treated groups were in a good general condition and showed a normal behaviour in acitivity, eating and growth. Animals treated with nandrolone for four weeks showed decreased activity and progressive diminution in their appetites. Some animals became morbid and weak during the experiment. While the animals left two weeks after arrest of nandrolone treatment, gradually regained their activity at the end of the experiment. Animals treated with nandrolone plus vitamin E were in a somewhat good general condition and had a moderate appetite compared with the nandrolone treated group. group I (Control group): Concerning the histological study: Sections of this group showed normal histological architecture of the cardiac muscle with centrally located oval basophilic nuclei and transverse striations. These transverse striations are due to the presence of longitudinally arranged myofibrils formed by alternating dark bands called A bands and light bands called I bands. Mitochondria are arranged in rows between the myofibrils. These cardiac muscle fibers are connected together by inter-calated disc which has a step like pattern. Delicate connective tissue (endomysium) surrounds the cardiac muscle fibers with small amount of collagen fibers. Concerning the histochemical study: The non treated control rats showed mild PAS positive reaction of the cardiac muscle fibers group II (Vitamin E – treated group): Concerning the histological study: Sections of this group showed the well known histological picture of rat myocardium with normal amount of collagen fibers in the endomysium. Concerning the histochemical study: There was a weak to mild PAS positive reaction of the cardiac muscle fibers. group III (Nandrolone – Treated group): Concerning the histological study: Sections of subgroup IIIA showed loss of normal architecture of cardiac muscle fibers that take a wavy appearance. These fibers showed pyknotic eccentric nuclei and loss of striation. Fragmented fibers with disorganized intercalated disc and obvious vacuolation were seen. Abundance of necrotic areas surrounded by fragmented and degenerated fibers were markedly seen. The sarcoplasmic reticulum and T- tubules were dilated. Mitochondria with ruptured membranes (moth eaten appearance) and ruptured cristae were also detected. The connective tissue endomysium appeared widened with dilated congested blood vessels and marked amount of collagen fibers. While sections of Subgroup IIIB showed improvement of some cardiac muscle fibers while others show focal areas of necrosis and pyknotic nuclei. Some of the myofibrils restored their normal appearance, but most of them were still degenerated. There is also abnormal distribution of the mitochondria which appeared degenerated. The intercalated disc was still disorganized Abnormal nucleus with peripheral condensed chromatin was also seen. The endomysium inbetween the fibers was widened with moderate amount of collagen fibers. Concerning the histochemical study: Sub group IIIA showed strong PAS positive reaction in most cardiac muscle fibers and weak reaction in some degenerated fibers. While (Subgroup IIIB) showed moderate to strong PAS positive reaction of the cardiac muscle fibers. group IV (Nandrolone and Vitamin E-treated group): Concerning the histological study: Sections of this group showed a noticeable protection of myofibers against the deleterious changes induced by nandrolone. The myocardium architecture is more or less normal with tiny vacuoles appearing in some muscle fibers. Most of nuclei appeared vesicular but few pyknotic nuclei are still seen in few fibers. Also intercalated disc appeared disorganized in some areas. The connective tissue endomysium is slightly widened with mild amount of collagen fibers. Concerning the histochemical study: There was moderate PAS positive reaction of the cardiac muscle fibers. from the foregoing, it is concluded that chronic administration of supra physiological doses of nandrolone resulted in marked histological and histochemical changes on rat cardiac muscle. These changes were partially reversible after cessation of treatment. Co-administration of vitamin E with nandrolone had marked protective effect. So, we recommend that nandrolone must be used under clinical supervision especially in the young misinformed athletes. Vitamin E supplementation with nandrolone is also advised to minimize its adverse effects on the cardiac muscle. |