Histologic study on the protective effect of alpha-lipoic acid in sciatic nerve neurotoxicity induced by cypermethrin in albino rats

This work was undertaken to study the possible protective role of ex-lipoic acid [ALA] in the sciatic nerve of rats intoxicated with the pesticide cypermethrin by histological and morphometric methods. Thirty adult male albino rats were randomly divided into five equal groups [six rats each]: group I [control group] received no treatment, group II received daily 1 ml of corn oil orally, group III received 100 mg/kg of oral ALA daily, group IV received oral cypermethrin [75 mg/kg] daily, and group V received both ALA and cypermethrin. After 5 days treatment, both sciatic nerves were dissected out from each animal, and then semithin and ultrathin sections were prepared for light and electron microscopic examinations. Morphometric and statistical analyses were also conducted, After cypermethrine administration, the sciatic nerve showed nerve damage particularly affecting the myelinated nerve fibers. The lesions were manifested as axonal damage and changes in the myelin sheath. Myelinated nerve fibers were swollen showing Wallerian degeneration. Ultrastructurally, myelin sheaths exhibited fragmentation, vacuolations, and hyalinization, Axoplasm displayed shrinkage, vacuolations, fragmentations, myelin figures, and intra-axonal wipe spaces, with swelling of Schwann cells. Unmyelinated fibers were minimally affected. Concomitant administration of ALA with cypermethrine displayed an observable protection against these changes. ALA showed a protective effect against sciatic neurotoxicity induced by cypermethrin in albino rats

Effect of aluminum on the histological structure of rats' cerebellar cortex and possible protection by melatonin

Aluminum [AL] is toxic to the central nervous system, and melatonin [MEL] reduces lipid peroxidation by its antioxidant activity. This study was carried out to investigate the histological changes in the cerebellar cortex of rats after AL treatment and to detect any possible protective role of MEL when given concomitantly with AL. This study used 50 adult male albino rats, randomly divided into five equal groups. Group I: control group; group II: received daily intraperitoneal [i.p.] injection of 1/2 ml 0.9% saline containing 2% ethanol; group III: received daily i.p. injection of MEL at 10 mg/kg bw dissolved in 1/2 ml 0.9% saline plus 2% ethanol; group IV: received daily i.p. injection of aluminum chloride at 10 mg/kg bw dissolved in 1/2 ml saline; group V: received both AL and MEL. After 2 months of treatment, the cerebellum was dissected out from each animal and was processed for light and electron microscopic studies. Morphometric and statistical analysis were conducted. After AL administration, the cerebellum exhibited significant reduction in the number of Purkinje cells and prominent peri neuronal spaces in the molecular layer around basket and stellate cells. Ultrastructurally, some of the few encountered Purkinje cells were shrunken with dense cytoplasm, ill-distinct nuclei, and swollen mitochondria with ruptured membranes and cristae. Granule cells revealed increased condensation of their nuclear chromatin. Concomitant administration of MEL with AL displayed an observable protection against these changes. MEL may have a protective role against AL-induced cerebellar toxicity

Advances in tissue engineering: current status and future prospects

Recent developments in biomedical engineering as well as basic biology and medicine have enabled us to induce cell-based regeneration of body tissue aided by self-repairing tissues or substitute biological functions of damaged organs with cells. For successful tissue regeneration, it is important to provide cells with an environment suitable for the induction of cell-based tissue regeneration. Tissue engineering is a newly emerging biomedical technology providing the potential to create the environment for tissue regeneration with various biomaterials. This study presents an overview of recent researches and clinical data on tissue regeneration based on tissue engineering, briefly explaining the key technologies of tissue engineering

Histological and immunohistochemical study on rat spleen in experimentally induced liver cirrhosis

The present study aimed to examine the histological changes in the spleen of rats with liver cirrhosis, and to determine the immunohistochemical expression of endothelial nitric oxide synthase [e-NOS], and its upstream effectors; tumor necrosis factor [TNF-alpha] and vascular endothelial growth factor [VEGF]. Twenty male adult albino rats were divided into two equal groups. The first was control. In the second group, liver cirrhosis was induced by intraperitoneal [ip] injection of thioacetamide 200 mg/kg twice weekly for 12 weeks. Splenic index [spleen weight / body weight] was determined and the spleens of rats which developed liver cirrhosis were subjected to the following stains: hematoxylin and eosin [H and E], silver impregnation, and immunostaining with specific antibodies for e-NOS, TNF-alpha and VEGF. Quantitative assessments were carried out using image analyzer with statistical analysis of the results. Splenic sections of cirrhotic rats showed in addition to congestion of venous sinuses, significant increase in reticular fibers in capsule and trabeculae as well as throughout the red pulp. The percentages of red pulp and fibrous trabeculae areas were significantly higher in cirrhotic rats, while the percentage of the white pulp areas was significantly smaller. Immunohistochemical staining of both e-NOS and TNF-alpha in spleen sections of group II rats were significantly lower than control, while VEGF immunostaining was significantly higher. Splenomegaly in liver cirrhosis was not only congestive but there was also significant increase of reticular fibers, red pulp area and angiogenesis. Moreover, nitric oxide [NO] reduction resulting from suppression of e-NOS and TNF-alpha seen in this study contributed to the increased volume of the spleen

Protective effect of Ginkgo biloba against experimental cardiotoxicity induced by isoproterenol in adult male albino rats a histological and biochemical study

The present study was designed to investigate whether Ginkgo biloba [GB] might protect the heart against myocardial injury induced by isoproterenol [ISO] on the basis of its effects on biochemical and histological parameters. Twenty four adult male albino rats [180-200 g] were used in this study. They were divided into 4 equal groups of six rats each. Group I was the control group and group II received ISO [85 mg/kg body weight [bw], subcutaneously [S.C.] for two consecutive days to induce myocardial injury. Group III received GB [200 mg/kg bw] orally by gastric gavage daily for 21 days while group IV received GB [200 mg/kg bw] orally daily for 21 days in addition to ISO [85 mg/kg bw], S.C. on the 20th and 21st day from starting GB. After 24 hours, rats were sacrificed and the levels of cardiac marker enzymes [creatine kinase-CK] and its myocardial isoenzyme [CK-MB]] were assessed in serum. Heart specimens were processed for light and electron microscopic examination. Administration of GB before ISO significantly prevented ISO-induced elevation of serum cardiac marker enzymes. Light and electron microscopic findings of the heart pretreated with GB revealed a well preserved normal morphology of cardiac muscle with minimal evidence of myocardial injury when compared to ISO-treated hearts. This study demonstrated that GB had a significant effect in the protection of heart against myocardial injury induced by ISO. This beneficial effect was mostly related to its antioxidant property. The results of the present investigation may trigger an interest towards the use of GB in myocardial infarction