Articles: manganese.
-
Review Meta Analysis
Plasma nutrient status of patients with Alzheimer's disease: Systematic review and meta-analysis.
Alzheimer disease (AD) patients are at risk of nutritional insufficiencies because of physiological and psychological factors. Nutritional compounds are postulated to play a role in the pathophysiological processes that are affected in AD. We here provide the first systematic review and meta-analysis that compares plasma levels of micronutrients and fatty acids in AD patients to those in cognitively intact elderly controls. A secondary objective was to explore the presence of different plasma nutrient levels between AD and control populations that did not differ in measures of protein/energy nourishment. ⋯ The lower plasma nutrient levels indicate that patients with AD have impaired systemic availability of several nutrients. This difference appears to be unrelated to the classic malnourishment that is well known to be common in AD, suggesting that compromised micronutrient status may precede protein and energy malnutrition. Contributing factors might be AD-related alterations in feeding behavior and intake, nutrient absorption, alterations in metabolism, and increased utilization of nutrients for AD pathology-related processes. Given the potential role of nutrients in the pathophysiological processes of AD, the utility of nutrition may currently be underappreciated and offer potential in AD management.
-
Manganese (Mn) is an essential trace element that is required for normal brain functioning. However, excessive intake of Mn has been known to lead to neuronal loss and clinical symptoms resembling idiopathic Parkinson's disease (IPD), whose precise molecular mechanism remains largely elusive. In the study, we established a Mn-exposed rat model and identified a mitochondrial protease, the mature form of high temperature requirement A2 (HtrA2/Omi), which was significantly upregulated in rat brain striatum after Mn exposure. ⋯ In addition, blockage of HtrA2 activity with UCF-101 restored Mn-induced reduction in XIAP expression. Finally, we observed that UCF-101 treatment ameliorated Mn-induced apoptosis in PC12 cells. Collectively, these findings suggested that upregulated HtrA2 played a role in Mn-induced neuronal death in brain striatum.
-
J Toxicol Env Heal A · Jan 2014
Anthocyanin-rich açaí (Euterpe oleracea Mart.) extract attenuates manganese-induced oxidative stress in rat primary astrocyte cultures.
Manganese (Mn) is an essential element for human health. However, at high concentrations Mn may be neurotoxic. Mn accumulates in astrocytes, affecting their redox status. ⋯ A larger quantity of açaí extract exacerbated the effects of Mn on these parameters except with respect to lipid peroxidation assessed by means of F₂-isoprostanes. These studies indicate that at nutritionally relevant concentration, anthocyanins obtained from açaí protect astrocytes against Mn neurotoxicity, but at high concentrations, the "pro-oxidant" effects of its constituents likely prevail. Future studies may be profitably directed at potential protective effects of açaí anthocyanins in nutraceutical formulations.
-
J Toxicol Env Heal A · Jan 2014
Açaí (Euterpe oleracea Mart.): a tropical fruit with high levels of essential minerals-especially manganese-and its contribution as a source of natural mineral supplementation.
Açaí is a fruit from the Brazilian Amazon region, with an exotic flavor, possessing high antioxidant and anti-inflammatory properties. Based on these properties, the fruit is classified as one of the new "super fruits." The mean daily consumption of açai pulp may reach 300 ml in several Brazilian regions. Further, this fruit is also gaining popularity in Europe and North America. ⋯ Consequently, Mn intake may surpass the permitted daily maximum intake of 11 mg, which leads to a special concern, particularly for children, vegetarians, and individuals with anemia, since iron (Fe) absorption is impaired by Mn. Our findings demonstrate that this fruit is a potential source of several nutrients and a good dietary supplement to resolve malnutrition problems. However, due to the expressive levels of Mn, further studies are necessary to evaluate potential adverse effects associated with açaí consumption.
-
Manganese neurotoxicity is associated with motor and cognitive disturbances known as Manganism. However, the mechanisms underlying these deficits remain unknown. Here we investigated the effects of manganese intoxication on motor and non-motor parkinsonian-like deficits such as locomotor activity, motor coordination, anxiety and "depressive-like" behaviors. ⋯ Electrophysiological results show that, while majority of GP and STN neurons discharged regularly in controls, manganese increased the number of GP and STN neurons discharging irregularly and/or with bursts. Biochemical results show that manganese significantly decreased tissue levels of norepinephrine and serotonin with increased metabolism of dopamine in the striatum. Our data provide evidence that manganese intoxication is associated with impaired neurotransmission of monoaminergic systems, which is at the origin of changes in basal ganglia neuronal activity and the manifestation of motor and non-motor deficits similar to those observed in atypical Parkinsonism.