Removing reproductive organs extends male lifespan but not female, study shows
A new study reveals that eliminating germline tissue—which produces sperm and eggs—extends lifespan in male nematodes but offers no survival benefit to females. The finding challenges assumptions about aging and reproduction, suggesting that sex-specific biology demands different approaches to longevity research and may influence future strategies in regenerative medicine and aging therapeutics.
Originaltitel: Sex-specific growth and lifespan effects of germline removal in the dioecious nematode <em>Caenorhabditis remanei</em>
<p>Germline regulates the expression of life-history traits and mediates the trade-off between reproduction and somatic maintenance. However, germline maintenance in itself can be costly, and the costs can vary between the sexes depending on the number of gametes produced across the lifetime. We tested this directly by germline ablation using glp-1 RNA interference (RNAi) in a dioecious nematode Caenorhabditis remanei. Germline removal strongly increased heat-shock resistance in both sexes, thus confirming the role of the germline in regulating somatic maintenance. However, germline removal resulted in increased lifespan only in males. High costs of mating strongly reduced lifespan in both sexes and obliterated the survival benefit of germline-less males even though neither sex produced any offspring. Furthermore, germline removal reduced male growth before maturation but not in adulthood, while female growth rate was reduced both before and especially after maturation. Thus, germline removal improves male lifespan without major growth costs, while germline-less females grow slower and do not live longer than reproductively functional counterparts in the absence of environmental stress. Overall, these results suggest that germline maintenance is costlier for males than for females in C. remanei.</p>