Effect of selenium in ameliorating the effect of induced perinatal hypothyroidism on postnatal rat cerebellar cortex development: a histological and immunohistochemical study

Background: Thyroid hormone plays a key role in the development of the cerebellar cortex. Selenium is a nutritional element with antioxidant and neuroprotective properties

Aim: The aim of this study was to investigate the effect of selenium on the structural impairment of postnatal rat cerebellar cortex development induced by perinatal experimental hypothyroidism

Materials and methods: Pups from 20 pregnant rats were divided into four equal groups: group I: negative control group, group II: methimazole-induced hypothyroid group, group III: selenium-supplemented hypothyroid group, and group IV: selenium-supplemented group [positive control]. Treatment continued from gestational day 14 to postnatal day [P] 14. At P7, P14, and P28, blood samples were collected for assessment of serum thyroid hormone and right cerebellar hemisphere specimens were processed for histological, immunohistochemical, and morphometric procedures

Results: Pups of hypothyroid group showed a retarded postnatal cerebellar cortex development, more apparent at P7 and P14, evidenced by increased thickness of the external granular layer and delayed alignment and differentiation of Purkinje cells in addition to reduced proliferating cell nuclear antigen and increased caspase 3-immunoreactivity. At P28, dark cell degeneration of most Purkinje cells was observed. A significant decrease in the thickness of the molecular and internal granular layers and of the number and surface area of Purkinje cells was observed in all postnatal ages studied. Glial fibrillary acidic protein immunostaining showed increased positive astrocytes with twisting and thickening of their glial fibers. Selenium caused a marked amelioration of most of these structural alterations

Conclusion: Perinatal hypothyroidism impaired postnatal cerebellar cortex development. Selenium should be used as a dietary supplement during pregnancy, particularly in hypothyroid conditions

Light and electron microscopic study on the effect of malathion on the adrenal gland of adult male albino rat and the possible protective role of vitamin [C]

Malathion is one of the organophosphorus insecticides widely used in agricultural and household applications to control pests. Actually, the studies of the effect of malathion on the adrenal%land are still limited, Vitamin C is the major water soluble antioxidant and free radical scavenger within the body. The aim of the work is to study the effect of chronic exposure to malathion on the adrenal gland. We also aim to study the possible protective effect of vitamin C in attenuating the nossible malathion induced changes. A total number of 30 adult male albino rats aged three months was used in the present study. Rats were randomly divided into three groups: l The first group [GI]: 10 rats were used as control 2- The second group [GH]: 10 animals were used as malathion treated group. 3- The third group [GUI]: 10 rats were used as malathion/vitamin C treated group. Commercial malathion was used, dissolved in distilled water and given orally by intragastric tube in a dose of 100 mg/kg/dayfor 2 months. Vitamin C was given orally by intragastric tube in a dose of 20 mg/WOgm/day for 2 months. After two months, the animals of the three groups were anaesthetized with ether inhalation and the suprarenal glands were dissected out and processed for light and electron microscopic examination. In malathion treated rats, there was cellulae disturbance in the arrangement of the adrenal gland. The cells of the cortex and medulla, showed irregular nuclei and apparent increase in the cytoplasmic vacuolation. Cortical and medullary blood capillaries were dilated and engorged with blood. Immunohistochemical staining for Caspase-3, showed many caspase-3 positive cells in the cortex and medulla. Ultrastructurally, degenerative changes were observed in the cortical and medullary cells in the form of cytoplasmic vacuolation, mitochondria! degeneration and increased lipid droplets. These changes were partially resolved by coadministration of vitamin C. Malathion had a harmful effect on adrenal gland so, it leads to impairment of its function in producing various hormones. This effect could be partially resolved, by concomitant administration of vitamin [C]. So, it is advisable to give vitamin [C] to those exposed to malathion

Chronic effect of aspartame versus stevioside on the cerebellar cortex of the adult albino rat: a histological and immunohistochemical study

Sweeteners have evolved rapidly over the last 20 years and are added to a wide variety of food items, drinks, drugs, and hygiene products. Aspartame is the most frequently used artificial sweetener. In contrast, stevioside is a sweet herb that seemed to be a promising natural candidate to replace artificial sweeteners but was found to have hazardous effects on the male reproductive system. The aim of this work was to compare between the histological changes in the cerebellar cortex of adult rats after administration of aspartame and stevioside for 6 months. The reversibility of these changes was also evaluated. A total of 25 albino rats aged 3 months were used in this study. They were divided into five groups comprising five rats each. The first group was the control group. Rats in the second group were given stevioside at a dose of 8.6 mg/day for 6 months. Rats in the third group were given stevioside for 6 months and were then allowed 1 month for recovery. Rats in the fourth group were given aspartame at a dose of 20 mg/day for 6 months. Rats in the fifth group were given aspartame for 6 months and were then allowed 1 month for recovery. Specimens of the cerebellar cortex were processed for H and E and subjected to immunohistochemical staining for glial fibrillary acidic protein [GFAP] and caspase-3 and electron microscopic study. Morphometric and statistical analyses were performed to count the number of Purkinje cells, the number of granular cells, and the number of GFAP and caspase-3 immunostained cells. The present study showed degenerative changes in the Purkinje and granular cell layers in both the aspartame-treated and stevioside-treated groups. This was confirmed by a significant increase in caspase-positive cells and a significant decrease in cell number. Moreover, there was marked increase in the number of astrocytes in areas of degeneration. This was confirmed by a significant increase in GFAP immunostaining. Recovery from stevioside was better than that from aspartame, as evidenced by the normal histological appearance of Purkinje cells and less vacuolated neuropils. This was supported by a significant increase in the number of neurons, significant decrease in caspase-positive cells, and significant decrease in GFAP immunostaining in the recovery group from stevioside compared with the recovery group from aspartame. Cessation of stevioside gives better results and leads to better improvement of the histological picture of the cerebellar cortex compared with cessation of aspartame

Effect of pre and postnatal exposure to lead acetate on the kidney of male albino rat: a light and electron microscopic study

Lead is a common environmental pollutant to which we are exposed every day and which can be incorporated in various body tissues. Exposure to lead is still a major medical problem in both environmental and occupational settings. This study was designed to elucidate the morphologic changes in the kidney of male albino rats after pre and postnatal lead exposure. A total number of 6 adult female pregnant albino rats were used in this study. Two of these females were given saline by intraperitoneal injection at late pregnancy till weaning. Ten of their offsprings served as control [Group I]. They were given saline for another one month then sacrificed. Four of the pregnant females were given lead acetate in a dose of 10mg/kg/day dissolved in saline by intraperitoneal injection at late pregnancy from day 16 till weaning. Twenty of their offsprings were divided into two groups. Group II [Ten animals] received lead acetate after weaning, in the same dose by intraperitoneal injection for one month then sacrificed. Group III [Ten animals] were left for one month after weaning without injection then sacrificed to study lead withdrawal. The specimens were obtained from the kidney and processed for examination by light, transmission and scanning electron microscopes. It was observed that treatment with lead disrupted the normal histological structure of the kidney.There was degenerative changes in the form of increase in the size of the renal corpuscles, thickening in the glomerular basement membrane and extensive vacuolation of the tubular lining cells. Mild regression of the previous findings was detected in the recovery group. Pre and posrnatal lead exposure is hazardous and has toxicological consequences affecting the kidney of young male albino rat. There was mild regression after one month of lead cessation