Laboratory of Seminology and Reproductive Immunology, Training Centre in Andrology of the European Academy of Andrology, Dept of Medical Physiopathology, University of Rome `La Sapienza', Policlinico Umberto I, 00161, Roma, Italy
Correspondence: E-mail: andrea.lenzia{at}uniroma1.it
![]() |
Introduction |
---|
![]() ![]() ![]() |
---|
We read with interest the paper by Ollero and colleagues (Ollero et al., 2001). They studied reactive oxygen species production and its effect on DNA and lipid concentration of the human sperm membrane. The findings are very interesting. We obtained similar results on the differences in DNA fragmentation between mature and immature sperm, separated by swim-up and studied using the same system (Spanò et al., 1999
).
However, we noted the finding of a higher concentration of docosahexaenoic acid (DHA) in immature germ cells and sperm compared with mature sperm. Some previous publications (Zalata et al., 1998; Lenzi et al., 2000
) have found the opposite, i.e. a higher concentration in mature sperm. This contrasting result may be due to variations in the separation techniques used by ourselves (Gandini et al., 1999
) and Ollero et al.
This difference also has an impact on membrane fluidity. One would expect to see improved fluidity with a higher DHA concentration in the mature cells, as in fact is stated by Ollero et al. Their finding regarding the reduction of DHA is in contrast with both the well-established increase in unsaturated fatty acids in mature sperm (Lenzi et al., 1996,1998
,2000
; Ollero et al., 2001
) and the need for a highly fluid membrane to achieve sperm maturation, motility and fertilization ability.
I would be interested to know Ollero et al.'s comments on this subject.
![]() |
References |
---|
![]() ![]() ![]() |
---|
Lenzi, A., Picardo, M., Gandini, L. and Dondero, F. (1996) Lipids of sperm plasma membrane: from polyunsaturated fatty acid considered as markers of sperm function to possible scavenger therapy. Hum. Reprod. Update, 2, 246256.
Lenzi, A., Gandini, L. and Picardo, M. (1998) A rationale for glutatione therapy. Debate on: is antioxidant therapy a promising strategy to improve human reproduction? Hum. Reprod., 13, 14191424.[ISI][Medline]
Lenzi, A., Gandini, L., Maresca, V., Rago, R., Sgrò, P., Dondero, F. and Picardo, M. (2000) Fatty acid composition of spermatozoa and immature germ cells. Mol. Hum. Reprod., 6, 226231.
Ollero, M., Gil-Guzman, E., Lopez, M.C., Sharma, R.K., Agarwal, A., Larson, K., Evenson, D., Thomas, A.J. Jr and Alvarez, J.G. (2001) Characterization of subset of human spermatozoa at different stages of maturation: implications in the diagnosis and treatment of male infertility. Hum. Reprod., 16, 19121921.
Spanò, M., Cordelli, E., Leter, G., Lombardo, F., Lenzi, A. and Gandini, L. (1999) Nuclear chromatin variation in human spermatozoa undergoing swim-up and cryopreservation evaluated by flow cytometric sperm chromatin structure assay. Mol. Hum. Reprod., 5, 2937.
Zalata, A.A., Christophe, A.B., Depuydt, C.E., Schoonjans, F. and Comhaire, F.H. (1998) The fatty acid composition of phospholipids of spermatozoa from infertile patients. Mol. Hum. Reprod., 4, 111118.[Abstract]