In a discovery that could reshape our understanding of aging and blood disorders, Japanese researchers have uncovered how a family of natural antioxidant proteins helps maintain the delicate balance of our blood system throughout life. The findings, published in the journal Blood, point to potential new strategies for addressing age-related decline in blood and immune system function.
The research team at Osaka University focused on selenoproteins – a group of 25 different enzymes that help protect cells from oxidative damage. Their work reveals these proteins play an unexpectedly crucial role in maintaining healthy blood stem cells and immune system development, particularly in B cells that produce antibodies.
“We observed that aged HSCs frequently display impaired selenoprotein synthesis, but it was unclear how this could contribute to cell aging and if it could be reversed,” said Yumi Aoyama, co-lead author of the study from Osaka University.
The research provides new insights into why blood stem cells become less effective as we age. When selenoprotein production was disrupted in mice, their blood stem cells showed limited ability to self-renew – a key characteristic of aging. The effects were particularly pronounced in B cells, an important type of immune cell, while other immune cells called myeloid cells were largely unaffected.
This selective impact on different cell types offers important clues about how aging affects the blood and immune systems differently. The research team found that without proper selenoprotein function, dangerous molecules called lipid peroxides begin to accumulate in certain cell types, leading to cellular damage consistent with aging.
“The most notable results of the knockout included B lymphocytopenia, which means there were fewer B cells than expected,” explained Hiromi Yamazaki, the study’s other co-lead author. This finding mirrors what happens in many age-related blood disorders.
The implications extend beyond just understanding how blood cells age. The research team, led by senior author Daichi Inoue, discovered that dietary vitamin E could help protect blood cell production and repair impaired B cell development in their experimental model. This suggests potential dietary interventions could help maintain healthy blood and immune system function with age.
“Our data suggest clear lineage-specific effects when the protective role of selenoproteins is lost,” said Inoue. “These enzymes are critical for counteracting the lipid peroxides that accumulate during the aging process.”
The findings are particularly relevant given the growing global aging population and increasing interest in interventions that could maintain health into later life. By understanding how selenoproteins protect specific blood cell types, researchers may be able to develop targeted treatments for age-related blood and immune disorders.
The research also revealed an unexpected flexibility in blood cell development – when selenoprotein production was disrupted, some developing B cells showed signs of switching to become myeloid cells instead. This plasticity in cell fate could have important implications for understanding both normal aging and blood disorders.
As research continues, the team’s findings open new avenues for investigating how dietary factors and cellular antioxidant systems might be harnessed to maintain healthy blood and immune function throughout life. The study suggests that maintaining proper selenoprotein function could be an important factor in preventing or treating age-related decline in blood system function.
The complete findings are available in the journal Blood under the title “Selenoprotein-Mediated Redox Regulation Shapes the Cell Fate of HSCs and Mature Lineages.”