Suppressive effect of molybdenum on hepatotoxicity of N-nitrosodiethylamine in rats

Mechanistic insights into the treatment of iron-deficiency anemia and arthritis in humans with dietary molybdenum

In the last few decades, there has been a resurgence in interest in the use of dietary supplements to treat diseases in humans and molybdenum has the potential to be used therapeutically. In humans, dietary molybdenum has been shown to treat iron-deficiency anemia and it may treat joint pain in arthritis. It has been proposed that the anti-anemic and tentative anti-arthritic properties of molybdenum are because it is increasing the activity of one or more mammalian molybdoenzymes. Molybdenum forms part of the active site of these enzymes. Despite this, it is unlikely that a molybdenum deficiency can develop in humans that are on an oral diet and not exposed to unsafe levels of a molybdenum antagonist. Therefore, the underlying mechanism by which dietary molybdenum treats or may treat these diseases is currently not known. This minireview examines three possible underlying mechanisms. It investigates the possibility that molybdenum: increases the quantity of active mammalian molybdoenzymes, restores or partially restores activity to malfunctioning mammalian molybdoenzymes, or blocks nuclear receptors, in cells. The examination of these mechanisms has provided an impression of the mechanism by which molybdenum treats iron-deficiency anemia and may treat arthritis; and hypothesize uses of molybdenum for other human diseases.

Silymarin modulates the oxidant-antioxidant imbalance during diethylnitrosamine induced oxidative stress in rats

Oxidative stress is a common mechanism contributing to initiation and progression of hepatic damage in a variety of liver disorders. Hence, there is a great demand for the development of agents with potent antioxidant effect. The aim of the present investigation is to evaluate the efficacy of silymarin as a hepatoprotective and an antioxidant against diethylnitrosamine induced hepatocellular damage. Single intraperitoneal administration of diethylnitrosamine (200 mg/kg) to rats resulted in significantly elevated levels of serum aspartate transaminase (AST) and alanine transaminase (ALT), which is indicative of hepatocellular damage. Diethylnitrosamine induced oxidative stress was confirmed by elevated levels of lipid peroxidation and decreased levels of superoxide dismutase (SOD), catalase, glutathione peroxidase, glutathione reductase (GR) and glutathione-S-transferase (GST) in the liver tissue. The status of non-enzymic antioxidants like, vitamin-C, vitamin-E and reduced glutathione (GSH) were also found to be decreased in diethylnitrosamine administered rats. Further, the status of membrane bound ATPases was also altered indicating hepatocellular membrane damage. Posttreatment with the silymarin (50 mg/kg) orally for 30 days significantly reversed the diethylnitrosamine induced alterations in the liver tissue and offered almost complete protection. The results from the present study indicate that silymarin exhibits good hepatoprotective and antioxidant potential against diethylnitrosamine induced hepatocellular damage in rats.