Gonadal transcriptome alterations in response to dietary energy intake: sensing the reproductive environment.
Level 5 - mechanism / opinion, no new human data
Animal research (rodent model)
PubMed 19127293 · doi:10.1371/journal.pone.0004146
What was done
Starting at four months of age, male and female rats were subjected for six months to a 20% or 40% caloric restriction (CR) diet, intermittent fasting (every-other-day feeding), or a high fat-high glucose (HFG) diet. The transcriptional activity of gonadal responses was measured at individual gene and parametric functional levels, along with plasma sex hormone ratios.
What was found
The abstract reports relative comparisons but no absolute gene counts or quantitative hormone levels. Females showed a higher degree of coherency in gonadal gene alterations to CR than males. Under intermittent fasting, the number of significantly regulated genes in males was almost 5 times greater than in females, and these males exhibited the highest plasma testosterone-to-estrogen ratio.
Why it matters
This study demonstrates marked sex-specific gonadal transcriptional and endocrine responses to energy restriction and intermittent fasting in rodents.
Limits
The study was conducted in a rodent model, limiting direct extrapolation to human reproductive biology. The abstract does not provide the total sample size (n), exact expression numbers, or functional fertility endpoints such as mating success or live birth rates.
Cited by
- supports In female rats, 20% daily calorie restriction does not alter estrous cycles, whereas 40% daily calorie restriction causes them to stop cycling and lose significant body fat.