A scientific team made up of researchers from the Baylor College of Medicine has carried out a highly relevant study published in the journal Science. The objective of the study was to develop the first cellular aging atlas of the fruit fly, thus providing a detailed view of the aging process in different cell types of this insect.
The atlas, known as the Aging Fly Cell Atlas (AFCA), is the result of extensive research that thoroughly characterized the aging process in 163 different cell types of the fruit fly. The results obtained revealed that each cell type ages differently, following specific and distinctive patterns. This discovery is of great importance, as it provides a deeper understanding of the mechanisms underlying cellular ageing.
The research team, led by Professor Hongjie Li, an expert in Molecular Genetics at Baylor, was able to characterize the 163 cell types with high reliability throughout four different stages of the fly’s life. “We discovered that fat or adipose cells significantly increase their nuclear number during aging. Our in vivo data show that the increase is due to an atypical event, in which these cells undergo nuclear cleavage without DNA replication,” says the professor.
Aging of Fat and Liver Cells
Furthermore, the study revealed that the cell types that age most rapidly are fat cells and liver cells, which play a crucial role in the control of metabolism. These results suggest that this pattern can also occur in humans. According to Li, if the aging of these cell types can be slowed down, there could be considerable health benefits.
The Aging Fly Cell Atlas also provided information on how aging affects the cellular composition of the fly as a whole. The researchers developed aging clock models for 64 cell types and determined which cell types and genes can be used to more accurately predict biological age. This approach made it possible to analyze specific biological characteristics of individual cells as the flies aged naturally in the laboratory.
The analysis focused on changes in gene expression, looking at how it altered as the flies aged compared to young flies. Four distinct features of cellular aging were examined: changes in cell composition, number of differentially expressed genes, variation in gene number, and decreased cell identity.
Calibrating the Biological Age
The study also highlighted that different cell types divergently contribute to the aging phenotype of a specific tissue. For example, in the reproductive system of female Drosophila, follicular cells were found to age rapidly, while germline cells aged more slowly. This indicates that the age-related decline in female fertility may be influenced primarily by aging follicular cells.
One of the highlights of the study is that the unique aging patterns discovered in fruit fly cells could be used to calibrate biological age, that is, the relative aging state of an organism, regardless of its chronological age. This could have significant implications for understanding the factors that influence aging and for the development of interventions aimed at slowing down the aging process and promoting healthy living.
The Fruit Fly Aging Atlas represents a valuable tool for research in the field of aging. According to study co-authors, the atlas provides a detailed map of how gene expression changes during aging in a wide range of fruit fly cell types. Since many of the identified genes have similar functions in humans, these data could help unravel the causes of various human diseases that arise later in life.
