OBJECTIVE: This study was designed to explore the relationship between men's age and DNA damage and apoptosis in human spermatozoa. DESIGN: Semen samples were collected from men between the ages of 20 and 57 years. Sperm DNA double-strand breaks were assessed using the neutral microgel electrophoresis (comet) assay, and apoptosis was estimated using the DNA diffusion assay. SETTING: Academic medical center. PATIENT(S): Sixty-six men aged 20 to 57 years were recruited from infertility laboratory and general populations and consented to donate a semen sample. Recruitment was determined by time and day of analysis; the only exclusions were for azoospermia, prostatitis, or prior cancer therapy. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): DNA damage and apoptosis in human sperm. RESULT(S): Age correlated with an increasing percentage of sperm with highly damaged DNA (range: 0-83%) and tended to inversely correlate with percentage of apoptotic sperm (range: 0.3%-23%). For example, percentage of sperm with highly damaged DNA, comet extent, DNA break number, and other comet measures was statistically significantly higher in men aged 36-57 years than in those aged 20-35 years, but percentage apoptosis was statistically significantly lower in the older group. Semen analysis showed percentage motility to be significantly higher in younger age groups. CONCLUSION(S): This study clearly demonstrates an increase in sperm double-stranded DNA breaks with age. Our findings also suggest for the first time an age-related decrease in human sperm apoptosis. These novel findings may indicate deterioration of healthy sperm cell selection process with age.
OBJECTIVE: This study was designed to explore the relationship between men's age and DNA damage and apoptosis in human spermatozoa. DESIGN: Semen samples were collected from men between the ages of 20 and 57 years. Sperm DNA double-strand breaks were assessed using the neutral microgel electrophoresis (comet) assay, and apoptosis was estimated using the DNA diffusion assay. SETTING: Academic medical center. PATIENT(S): Sixty-six men aged 20 to 57 years were recruited from infertility laboratory and general populations and consented to donate a semen sample. Recruitment was determined by time and day of analysis; the only exclusions were for azoospermia, prostatitis, or prior cancer therapy. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): DNA damage and apoptosis in human sperm. RESULT(S): Age correlated with an increasing percentage of sperm with highly damaged DNA (range: 0-83%) and tended to inversely correlate with percentage of apoptotic sperm (range: 0.3%-23%). For example, percentage of sperm with highly damaged DNA, comet extent, DNA break number, and other comet measures was statistically significantly higher in men aged 36-57 years than in those aged 20-35 years, but percentage apoptosis was statistically significantly lower in the older group. Semen analysis showed percentage motility to be significantly higher in younger age groups. CONCLUSION(S): This study clearly demonstrates an increase in sperm double-stranded DNA breaks with age. Our findings also suggest for the first time an age-related decrease in human sperm apoptosis. These novel findings may indicate deterioration of healthy sperm cell selection process with age.
Authors: María José Ruiz-López; Gerardo Espeso; Donald P Evenson; Eduardo R S Roldan; Montserrat Gomendio Journal: Proc Biol Sci Date: 2010-04-14 Impact factor: 5.349
Authors: Jonatan Axelsson; Jens Peter Bonde; Yvonne L Giwercman; Lars Rylander; Aleksander Giwercman Journal: Asian J Androl Date: 2010-03-29 Impact factor: 3.285
Authors: Yani Lu; Huiyan Ma; Jane Sullivan-Halley; Katherine D Henderson; Ellen T Chang; Christina A Clarke; Susan L Neuhausen; Dee W West; Leslie Bernstein; Sophia S Wang Journal: Am J Epidemiol Date: 2010-05-27 Impact factor: 4.897