Protective effects of estrogens and caloric restriction during aging on various rat testis parameters.
OBJECTIVE
To investigate the effects of 17beta-estradiol (E2), Peganum harmala extract (PHE) and caloric restriction (CR) on various testis parameters during aging.


METHODS
Twelve month-old male rats were treated for 6 months with either E2 or PHE, or submitted to CR (40%).


RESULTS
Our results show that estrogens and CR are able to protect the male gonad by preventing the decrease of testosterone and E2 levels as well as the decrease of aromatase and estrogen receptor gene expressions. Indeed, E2, PHE and CR treatments induced an increase in the superoxide dismutase activities and decreased the activity of testicular enzymes: gamma-glutamyl transferase, alkaline phosphatase, lactate deshydrogenase as well as the aspartate and lactate transaminases in aged animals. In addition, the testicular catalase and gluthatione peroxidase activities were enhanced in E2, PHE and CR-treated rats compared to untreated animals at 18 months of age. Moreover, the positive effects of estradiol, PHE and CR were further supported by a lower level of lipid peroxidation. Recovery of spermatogenesis was recorded in treated rats.


CONCLUSIONS
Besides a low caloric diet which is beneficial for spermatogenesis, a protective antioxydant role of estrogens is suggested. Estrogens delay testicular cell damage, which leads to functional senescence and, therefore, estrogens are helpful in protecting the reproductive functions from the adverse effects exerted by reactive oxygen species (ROS) produced in large quantities in the aged testis.
Hamden
Khaled
K
Department of Animal Ecophysiology, Faculty of Sciences, University of Sfax, PB 802, Sfax 3018, Tunisia.
Silandre
Dorothee
D
Delalande
Christelle
C
Elfeki
Abdelfattah
A
Carreau
Serge
S
D000375:Aging / Q000502:physiology*; D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D001141:Aromatase / Q000096:biosynthesis / Q000235:genetics; D031204:Caloric Restriction; D004958:Estradiol / Q000378:metabolism / Q000494:pharmacology; D004967:Estrogens / Q000494:pharmacology*; D015227:Lipid Peroxidation / Q000187:drug effects; D008297:Male; D018384:Oxidative Stress / Q000187:drug effects; D032443:Peganum / Q000737:chemistry; D010936:Plant Extracts / Q000494:pharmacology; D012313:RNA / Q000096:biosynthesis / Q000235:genetics; D051381:Rats; D017208:Rats, Wistar; D011960:Receptors, Estrogen / Q000096:biosynthesis / Q000235:genetics; D013737:Testis / Q000187:drug effects* / Q000201:enzymology / Q000254:growth & development*; D013739:Testosterone / Q000378:metabolism; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism
D000975:Antioxidants; D004967:Estrogens; D010936:Plant Extracts; D011960:Receptors, Estrogen; D017392:Thiobarbituric Acid Reactive Substances; D013739:Testosterone; D004958:Estradiol; D012313:RNA; D001141:Aromatase