Gender influence on manganese induced depression-like behavior and Mn and Fe deposition in different regions of CNS and excretory organs in intraperitoneally exposed rats.

Manganese (Mn) is an essential metal for mammals. It can modulate the action of endogenous substances, as neurotransmitters, but in excess also can trigger known neurotoxic effects. Many studies have been conducted assessing Mn neurotoxicity. However, Mn bioaccumulation in different brain tissues and behavior effects involving gender-specific studies are conflicted in the literature. Therefore, the aim of this work was to compare Mn effects, after 30days of intraperitoneal treatment, in male and female rats, submitted to forced swim and open field tests. After that, were evaluated Mn and Fe tissue levels in CNS, liver, and kidneys. Wistar rats were divided into saline, Mn 1mg/kg, Mn 5mg/kg, and imipramine (as forced swim control). Then, animals were euthanized by anesthesia overdose followed by decapitation and the collected tissue were striatum, hippocampus, brainstem, cortex, cerebellum, hepatic tissue, and renal tissue. Mn and Fe were determined by ICP-MS. There was a dose-dependent effect on accumulation of Mn in the cerebellum and brainstem to the dosage of 5mg/kg. In hippocampus there were bioaccumulation differences between gender and dose, and an increase of Fe in the groups exposed to Mn. Excess metals in the brain dissected has a strong influence on memory and learning processes and suggests pro-depressive effects, possibly triggered by the reduction of monoamines due to excessive metal bioaccumulation. It was concluded that, under this experimental design, Mn exposure cause metal deposition on dissected CNS, liver and kidney. There an effect at lower doses that was gender-dependent and males had more pronounced behavioral damage compared to females, although with increasing dose, females had an indication of motor damage.

Trace metal levels in serum and urine of a population in southern Brazil.

This study aimed to evaluate serum and urine concentrations of several trace metals of a non-directly exposed population in southern Brazil and establish reference values. Serum and urine samples were obtained from 240 volunteers (175 males and 65 females, age ranging from 18 to 74 years old). Levels of arsenic, chromium, cobalt, copper, lead, nickel, manganese and zinc were determined by means of dynamic reaction cell inductively coupled plasma mass spectrometry (DRC-ICP-MS). Comparison between genders resulted in no significant difference for all metals but serum copper, as concentrations are higher in females than males. For most metals assessed, a negative correlation between serum concentrations and age was found, but no significant correlation was found between urine concentrations and age.

Deficiency of macro- and micronutrients induced by Lentinula edodes.

Mushroom Lentinula edodes has been widely studied therapeutically. However, there is no data regarding its daily intake level safety. Since L. edodes has many active compounds known to bind to metals, we evaluated macro and micronutrients in liver and kidney of healthy rats after subchronic exposure to L. edodes. Rats were divided into four groups, receiving water and L. edodes at 100, 400 and 800 mg/kg/day. The treatment lasted 30 days. Essential elements (Zn, Cu, Mg, Fe, Mn, Se, Co, Mo, and Li) were analyzed in an inductively coupled plasma mass spectrometer. Our results demonstrated a significant decrease in Cu, Fe, Mn and Co levels in liver of rats receiving L. edodes at the highest doses. In kidney, Mn, Mo and Li concentrations significantly dropped in the groups exposed to the highest doses. In this way, an important point is revealed concerning the food safety from L. edodes, once its chronic and high consumption could contribute to macro and micronutrients deficiency. Additionally, we speculate that the daily use of L. edodes could be unsuccessful for patients in mineral therapy besides being able to be unsafe for individuals with some propensity to mineral deficiency.