Evidence for postnatal neurogenesis in the human amygdala
Sebastian S. Roeder, Petra Burkardt, Fabian Rost, Julian Rode, Lutz Brusch, Roland Coras, Elisabet Englund, Karl Håkansson, Göran Possnert, Mehran Salehpour, Daniel Primetzhofer, László Csiba, Sarolta Molnár, Gábor Méhes, Anton B. Tonchev, Stefan Schwab, Olaf Bergmann, Hagen B. Huttner
Abstract
Abstract The human amygdala is involved in processing of memory, decision-making, and emotional responses. Previous studies suggested that the amygdala may represent a neurogenic niche in mammals. By combining two distinct methodological approaches, lipofuscin quantification and 14 C-based retrospective birth dating of neurons, along with mathematical modelling, we here explored whether postnatal neurogenesis exists in the human amygdala. We investigated post-mortem samples of twelve neurologically healthy subjects. The average rate of lipofuscin-negative neurons was 3.4%, representing a substantial proportion of cells substantially younger than the individual. Mass spectrometry analysis of genomic 14 C-concentrations in amygdala neurons compared with atmospheric 14 C-levels provided evidence for postnatal neuronal exchange. Mathematical modelling identified a best-fitting scenario comprising of a quiescent and a renewing neuronal population with an overall renewal rate of >2.7% per year. In conclusion, we provide evidence for postnatal neurogenesis in the human amygdala with cell turnover rates comparable to the hippocampus.