title: Do age and sex impact on the absolute cell numbers of human brain regions?
abstract: What is the influence of sex and age on the quantitative cell composition of the human brain? By using the isotropic fractionator to estimate absolute cell numbers in selected brain regions, we looked for sex- and age-related differences in 32 medial temporal lobes (comprised basically by the hippocampal formation, amygdala and parahippocampal gyrus), sixteen male (29-92 years) and sixteen female (25-82); and 31 cerebella, seventeen male (29-92 years) and fourteen female (25-82). These regions were dissected from the brain, fixed and homogenized, and then labeled with a DNA-marker (to count all nuclei) and with a neuron-specific nuclear marker (to estimate neuron number). Total number of cells in the medial temporal lobe was found to be 1.91 billion in men, and 1.47 billion in women, a difference of 23 %. This region showed 34 % more neurons in men than in women: 525.1 million against 347.4 million. In contrast, no sex differences were found in the cerebellum. Regarding the influence of age, a quadratic correlation was found between neuronal numbers and age in the female medial temporal lobe, suggesting an early increase followed by slight decline after age 50. The cerebellum showed numerical stability along aging for both neurons and non-neuronal cells. In sum, results indicate a sex-related regional difference in total and neuronal cell numbers in the medial temporal lobe, but not in the cerebellum. On the other hand, aging was found to impact on cell numbers in the medial temporal lobe, while the cerebellum proved resilient to neuronal losses in the course of life.
authors.affiliation: Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: Ana V
authors.initials: AV
authors.lastname: Oliveira-Pinto
authors.affiliation: Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: Carlos H
authors.initials: CH
authors.lastname: Andrade-Moraes
authors.affiliation: Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: Lays M
authors.initials: LM
authors.lastname: Oliveira
authors.affiliation: Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: Danielle R
authors.initials: DR
authors.lastname: Parente-Bruno
authors.affiliation: Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: Raquel M
authors.initials: RM
authors.lastname: Santos
authors.affiliation: Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: Renan A
authors.initials: RA
authors.lastname: Coutinho
authors.affiliation: Brazilian Aging Brain Study Group, LIM 22, University of São Paulo Medical School, São Paulo, Brazil.|Hospital Israelita Albert Einstein, Brain Institute, São Paulo, SP, Brazil.
authors.forename: Ana T L
authors.initials: AT
authors.lastname: Alho
authors.affiliation: Brazilian Aging Brain Study Group, LIM 22, University of São Paulo Medical School, São Paulo, Brazil.|Discipline of Geriatrics, University of São Paulo Medical School, São Paulo, SP, Brazil.
authors.forename: Renata E P
authors.initials: RE
authors.lastname: Leite
authors.affiliation: Brazilian Aging Brain Study Group, LIM 22, University of São Paulo Medical School, São Paulo, Brazil.|Discipline of Geriatrics, University of São Paulo Medical School, São Paulo, SP, Brazil.
authors.forename: Claudia K
authors.initials: CK
authors.lastname: Suemoto
authors.affiliation: Brazilian Aging Brain Study Group, LIM 22, University of São Paulo Medical School, São Paulo, Brazil.|Department of Neurology and Pathology, University of California, San Francisco, USA.
authors.forename: Lea T
authors.initials: LT
authors.lastname: Grinberg
authors.affiliation: Brazilian Aging Brain Study Group, LIM 22, University of São Paulo Medical School, São Paulo, Brazil.
authors.forename: Carlos A
authors.initials: CA
authors.lastname: Pasqualucci
authors.affiliation: Brazilian Aging Brain Study Group, LIM 22, University of São Paulo Medical School, São Paulo, Brazil.|Discipline of Geriatrics, University of São Paulo Medical School, São Paulo, SP, Brazil.
authors.forename: Wilson
authors.initials: W
authors.lastname: Jacob-Filho
authors.affiliation: Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil. rlent@icb.ufrj.br.|National Institute of Translational Neuroscience, Ministry of Science and Technology, São Paulo, Brazil. rlent@icb.ufrj.br.|Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Av. Carlos Chagas 373, Sl. F1-31, Ilha do Fundão, Rio de Janeiro, CEP 21941-902, Brazil. rlent@icb.ufrj.br.
authors.forename: Roberto
authors.identifier: 0000-0002-8989-4009
authors.initials: R
authors.lastname: Lent
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging; D002452:Cell Count; D002531:Cerebellum / Q000166:cytology* / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009474:Neurons / Q000166:cytology* / Q000502:physiology; D012727:Sex Characteristics; D013702:Temporal Lobe / Q000166:cytology* / Q000502:physiology
keywords: Aging; Brain cellularity; Isotropic fractionator; Sexual dimorphism