Intracellular chemical imaging of human neuromeranin

Neuromeranin (NM) is a dark colored pigment synthesized within specific catecholamine-producing neurons in the human brain. It is of uncertain origin and exists as amorphous granules with a heterogeneous structure called NM granules. At the European Synchrotron Radiation Facility (ESRF) in Grenoble, the microchemical environment of NM in whole neurons from formalin-fixed and paraffin-embedded human substantia nigra sections was recently analyzed. It was found that concentrations of NM-associated elements increase in the developing brain, and that iron-rich microdomains colocalized with other elements within the pigment. Furthermore, intracellular speciation of sulfur in NM has revealed the presence of reduced sulfur compounds and various forms of oxidized sulfur compounds which have not previously been reported. For more information, see the paper, "Intracellular Chemical Imaging of the Developmental Phases of Human Neuromelanin Using Synchrotron X-ray Microspectroscopy", S. Bohic et al., Anal. Chem., Article ASAP, DOI: 10.1021/ac801817k