Stress and the Brain: An Emerging Role for Selenium

The stress response is an important tool in an organism’s ability to properly respond to adverse environmental conditions in order to survive. Intense acute or chronic elevation of glucocorticoids, a class of stress hormone, can have deleterious neurological effects, however, including memory impairments and emotional disturbances. In recent years, the protective role of the antioxidant micronutrient selenium against the negative impact of externally applied stress has begun to come to light. In this review, we will discuss the effects of stress on the brain, with a focus on glucocorticoid action in the hippocampus and cerebral cortex, and emerging evidence of an ability of selenium to normalize neurological function in the context of various stress and glucocorticoid exposure paradigms in rodent models.

Impact of chemotherapy on antioxidant micronutrient levels in patients with mature lymphoid malignancies

Introduction. Cancer treatments are now intense and are associated with nutritional deficiencies. The nutritional status of a patient may influence the tolerability of chemotherapy. Aim. We investigated the effects of chemotherapy on serum levels of trace elements (copper, iron, manganese, selenium, and zinc) and vitamins (A, C, and E) in patients with mature lymphoid malignancies (MLMs) at diagnosis and after 3 months. Material and methods. A case-control study of adults diagnosed with and treated for various MLMs. Thirty-nine cases and 39 age and sex-matched controls were recruited into this study. Venous blood samples were collected from the controls, cases at baseline and after 3 months of chemotherapy. Trace elements were determined by AAS while vitamins were determined by HPLC. Results. The levels of trace elements and antioxidant vitamins A and E were significantly higher (p<0.001) in cases than in controls while vitamin C was lower in cases compared to controls (p=0.005). After 3 months of treatment, 28 patients were available for analysis. There was a significant decline (p<0.001) in all the levels of trace elements and vitamins after chemotherapy. Conclusion. Chemotherapy is associated with a significant reduction in antioxidants levels in patients with MLMs.

Benefits of micronutrient supplementation for reducing the risk of wet age-related macular disease and diabetic retinopathy

Age-related macular disease and diabetic retinopathy are chronic degenerative diseases characterised by progressive visual impairment. In Europe, age-related macular disease accounts for over 15% of blindness in adults over 50 years of age, and although the burden of diabetic retinopathy in terms of vision impairment is lower, vision loss associated with diabetic retinopathy is increasing with the rising prevalence of diabetes mellitus and the ageing of the population. Late-stage age-related macular disease can be subdivided into dry (non-neovascular) or wet (neovascular or exudative) forms. The large Age-Related Eye Disease Study 2 showed that supplementation with antioxidant nutrients reduces choroids neovascularisation and reduces the risk of progression of neovascular age-related macular disease. Antioxidant micronutrient supplements have also shown promising results in preventing the pathogenesis of retinopathy in animal models of diabetes. Age-related macular disease and diabetic retinopathy are understood to share some common pathophysiological characteristics, suggesting that micronutrients have an important role in ocular health in both conditions. This article will review the current evidence for the utility of micronutrients in preventing the development and progression of neovascular age-related macular disease and diabetic retinopathy.