testosterone blocks leydig cell aging

Doug Skrecky oberon at vcn.bc.ca
Tue May 16 23:29:26 EST 2000

  Division of Reproductive Biology, Department of Biochemistry, Johns Hopkins
  University, School of Hygiene and Public Health, 615 North Wolfe Street,
  Baltimore, MD 21205, USA.
  Long-term suppression of Leydig cell steroidogenesis
  prevents Leydig cell aging.
  Proceedings of the National Academy of Sciences of the United States of
  America.  96(26):14877-81, 1999 Dec 21.
  Male aging is accompanied by reduced testosterone production
  by the Leydig cells, the
  testosterone-producing cells of the testis. The mechanism by
  which this occurs is unknown. Based on the observations that reactive oxygen
  is capable of damaging components of the steroidogenic pathway and that
  reactive oxygen is produced during steroidogenesis itself, we hypothesized
  that long-term suppression of steroidogenesis might inhibit or prevent
  age-related deficits in Leydig cell
  testosterone production. To test this, we administered
  contraceptive doses of testosterone to groups of young (3
  months old) and middle-aged (13 months old) Brown Norway rats via Silastic
  implants to suppress endogenous Leydig cell
  testosterone production. After 8 months, the implants were
  removed, which rapidly (days) restores the ability of the previously
  suppressed Leydig cells to produce
  testosterone. Two months after removing the implants, when
  the rats of the two groups were 13 and 23 months of age, respectively, the
  Leydig cells in both cases were found to produce
  testosterone at the high levels of young
  Leydig cells, whereas significantly lower levels were
  produced by the 23-month-old controls. Thus, by placing the
  Leydig cells in a state of steroidogenic "hibernation," the
  reductions in Leydig cell testosterone
  production that invariably accompany aging did not occur. If hormonal
  contraception in the human functions the same way, the adverse consequences
  of reduced testosterone in later life (osteoporosis, reduced
  muscle mass, reduced libido, mood swings, etc. ) might be delayed or

More information about the Ageing mailing list

Send comments to us at biosci-help [At] net.bio.net