Caenorhabditis elegans reproductive aging: Regulation and underlying mechanisms

Department of Molecular Biology, Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jeresy, USA.
genesis (Impact Factor: 2.02). 02/2011; 49(2):53-65. DOI: 10.1002/dvg.20694
Source: PubMed


Female reproductive decline is one of the first aging phenotypes in humans, manifested in increasing rates of infertility, miscarriage, and birth defects in children of mothers over 35. Recently, Caenorhabditis elegans (C. elegans) has been developed as a model to study reproductive aging, and several studies have advanced our knowledge of reproductive aging regulation in this organism. In this review, we describe our current understanding of reproductive cessation in C. elegans, including the relationship between oocyte quality, ovulation rate, progeny number, and reproductive span. We then discuss possible mechanisms of oocyte quality control, and provide an overview of the signaling pathways currently identified to be involved in reproductive span regulation in C. elegans. Finally, we extend the relevance of C. elegans reproductive aging studies to the issue of human female reproductive decline, and we discuss ideas concerning the relationship between reproductive aging and somatic longevity.

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Available from: Coleen Murphy
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    • "It is known that the germline and somatic reproductive system can signal to the rest of the soma to regulate lifespan through steroid hormones and the insulin signaling pathway (Hsin & Kenyon, 1999; Arantes-Oliveira et al., 2002; Yamawaki et al., 2010), and it is possible that EGR-1 is responding to these signals. As reproductive aging occurs relatively early in the worm lifespan (Luo & Murphy, 2011), it is likely that changes in signals from the germline represent an early molecular event in aging and could cause changes in many downstream genes in the soma. The fact that loss of egr-1 fully suppresses the longevity of germlineless mutants adds further evidence that egr-1 acts downstream of the germline to promote longevity. "
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