Induction of pancreatic thiol proteins by zinc protect against diabetogenic, oxidative and histological changes produced by arsenic toxicity in rats

Recent studies reported that, chronic arsenic exposure is always associated with an increase in the prevalence of diabetes mellitus. It is recognized that arsenic contributes to oxidative stress in several organs and systems including the islets of Langerhans through generation of reactive oxygen species [ROS]. So the current study was undertaken to elucidate the possible role of zinc as an antioxidant in the protection against diabetes mellitus induced by arsenic. Male Sprague-Dawley rats were given sodium arsenite daily at a dose of 1.5 mg/kg by gavage for 60 consecutive days. Another group of rats were injected I.P with zinc chloride 20 mg/kg for 2 days with one day interval, then was given sodium arsenite at a dose of 1.5 mg/kg by gavage every day for 60 consecutive days. Blood samples and pancreatic tissue specimens were collected from all the tested groups at the end of the experiment for biochemical evaluation and histological examination. The level of both thiobarbituric acid reactive substances [TBARs] and nitric oxide [NO] were significantly elevated in arsenite treated group as compared to control group. Hyperglycemia, hyper-insulinemia and low insulin sensitivity was observed. The activity of pancreatic thioredoxin reductase [TrxR] was lower than control group. Also, the levels of metallothionein [MT] and total glutathione [GSH] in pancreas increased significantly relative to the control group indicating the presence of stress and oxidative damage, respectively. Histological sections of pancreas of arsenic treated rats showed that a large number of islets were shrunken with low number of islet cells .The number of beta-cells decreased relative to the total islet cell number compared to control. Pre-treatment with zinc chloride before arsenic administration reversed the previous biochemical parameters and histological changes. The pancreatic TBARs and NO are reduced compared with arsenite treated group. Significant decrease in glucose level and decrease the level of insulin with increase insulin sensitivity was observed. Also pre-treatment with zinc resulted significant increase in the activity of TrxR, levels of MT and GSH. Zinc chloride prevented the reduction in beta-cell and islet cell number. Also it could restore the normal morphology of the islets. The current results clearly indicate the beneficial effects of zinc chloride in both controlling hyperglycemia and the protection of the pancreatic islet cells against oxidative stress in diabetes through induction of thiol proteins which may help setting a new direction toward the development of effective treatment of diabetes mellitus

Haemostatic and histopathological changes caused by alpha tocopherol and retinol palmitate

This work aimed to study the effect of alpha tocopherol [vitamin E] and retinol palmitate [vitamin A] on body weight, bleeding time, coagulation time, prothrombin time and kaolin partial thromboplastin of albino rat as well as to study the histopathological effect of these vitamins. A dose of 270 mg/kg/day of vitamin E and 500,000 IU/kg/day of vitamin A was given orally to albino rats for 21 days. The results showed that body weight was significantly decreased in both groups treated with vitamin E and vitamin A. It was found that vitamin E significantly increased the bleeding time and coagulation time, while vitamin A significantly increased the coagulation time only. However, the two groups treated with vitamin E and vitamin A showed a significant increase in prothrombin time, concentration and kaolin activated partial thromboplastin. The histopathological examination of liver, lung and kidney of autopsied animals revealed congestion, hemorrhage and mild inflammation, which were more severe in animals received vitamin E. In addition, the liver in both groups showed apoptosis and peripheral fatty changes

Histological and quantitative study of the effect of Eruca sativa seed oil on the testis of albino rat

Eruca Sativa [E.S] or Gargir seed oil is widely used in folk medicine. This study was conducted to investigate its possible effect on male rat fertility. Histological changes of the testis, level of testosterone hormone and sperm count were determined. The results revealed that administration of low dose of E.S. seed oil caused dilatation of the seminiferous tubules, proliferation of spermatogenic cells and increase of its mitotic activity. Increased number of sperms and epididymis weight, elevated level of testosterone hormone and hyperplasia of interstitial Leydig cells have also been noticed. DNA analysis revealed an increase of the percentage of haploid and decrease of diploid and tetraploid cells. Administration of E.S. seed oil at higher dose showed. decreased diameter of the seminiferous tubules, reduced spermatogenic activity and number of sperms . Also testosterone hormone level decreased and the interstitial cells appeared few. DNA analysis showed a reduction of the percentage of the haploid and increase of the percentage of diploid and tetraploid cells

Effect of "Ginseng" administration on the structural and ultrastructural changes produced by restraint stress in the liver cells of albino rats

This study aimed to assess the antistress effects of "Ginseng" in cases of chronic restraint stress by studying the structural and ultrastructural changes of the liver cells. Fifteen adult male albino rats were used. They were divided equally into 3 groups: control, stress and stress/Ginseng groups. Restraint stress was applied to both stress and stress/Ginseng groups 4 hours every other day for 4 weeks.15 mg Ginseng/kg/ was given to stress /Ginseng group every other day for 4weeks. Examination of liver specimens processed for both light and electron microscopic study revealed that chronic restraint stress causes fatty degeneration which may proceed to necrosis of the liver cells. A hepatoprotectective effect of ginseng was observed