Effects of progesterone and estradiol benzoate on superoxide dismutase activity in the brain of male rats

The activities of mitochondrial, manganese-containing superoxide dismutase (MnSOD) and cytoplasmic, copper-zinc-containing superoxide dismutase (CuZnSOD) were measured in subcellular fractions of whole brain homogenates prepared from intact and gonadectomized (GDX) male rats, untreated or treated subcutaneously (sc) with a single dose of 2 mg progesterone (P) and/or 5 mu g estradiol benzoate (EB). Neither MnSOD nor CuZnSOD was affected by the removal of the testes. Similarly, CuZnSOD activity was steady following systemic administration of P and/or EB to intact and GDX animals 2 h or 24 h prior to sacrifice. On the other hand, both P and EB suppressed MnSOD in the brain of either intact or GDX rats. These results suggest involvement of P and EB in the control of MnSOD activity in the brain of male rats

Effects of progesterone and estradiol benzoate on glutathione dependent antioxidant enzyme activities in the brain of female rats

The activities of glutathione dependent antioxidant enzymes were measured in subcellular fractions of whole brain homogenates prepared from ovariectomized (OVX) female rats, untreated or treated 2 h or 24 h prior to sacrifice with a single dose of 2 mg progesterone (P) or 5 mu g estradiol benzoate (EB). Glutathione peroxidase (GSH-Px) activity was not changed following systemic administration of EB, but P increased GSH-Px in the brain of OVX rats 24 h after the treatment. The activity of glutathione reductase (GR) was suppressed by EB short time, only 2 h following treatment, whereas P increased the enzyme activity 24 h after treatment. On the other hand, the activities of catalase (CAT) and glutathione-S-transferase (GST) were not changed following systemic administration of EB or P. The present work was carried out to study the involvement of ovarian steroids, especially P, in the control of GSH-Px and GR activities, and our results suggest that oxidative stress in the brain of female rats may be modulated by the level of progesterone

Glutathione-dependent antioxidant enzyme activities and glutathione content in the rat brain at different stages of oestrous cycle

Enzymatic activities of glutathione peroxidase, glutathione-S-transferase, glutathione reductase and catalase, as well as the glutathione content were measured in the brain tissue of regularly cycling rats at dioestrus, proestrus and estrus. The activity of glutathione peroxidase was found to be suppressed at proestrus, whereas that of catalase was increased at dioestrus. Glutathione transferase and glutathione reductase activities, as well as the glutathione content appeared to be stable during the oestrous cycle. These results suggest that, in the female rat, glutathione peroxidase and catalase activities in the brain tissue are influenced by the ovarian hormone status