Changes with sexual maturation and cryptorchidism of germ cell-linked polyunsaturated fatty acids

AYUZA ARESTI PL; FURLAND NE; ORESTI GM; AVELDAÑO MI

Rosario, Argentina

Congreso; XLII Reunión Nacional de la Sociedad Argentina de Investigación Bioquímica y Biología Molecular (SAIB); 2006

Sociedad Argentina de Investigación Bioquímica y Biología Molecular (SAIB)

The major polyunsaturated fatty acid (PUFA) of mature rat testis is known to be 22:5n-6. The aim of this work was to study how this fatty acid is accrued from postnatal to sexually mature rat testis as an acyl group of glycerophospholipids (GPL), and to determine in adult rats how these GPL are affected by cryptorchidism. Before the onset of spermatogenesis, 20:4n-6 was the most abundant PUFA in testicular choline and ethanolamine glycerophospholipid (CGP, EGP) in both their major subclasses (phosphatidyl and plasmenyl). Both EGPs contained a significant proportion of 22:6n-3. This high 22:6n-3 was restricted to the prepuberal age of the testis, gradually decreasing with sexual maturation. Concomitantly with the population of the testis with germ cells, the amount of 22:5n-6 increased in both CGP and EGP, to become the major PUFA of testis and remain so throughout the adult life of the rats, 20:4n-6 remaining in a modest second place. With cryptorchidism, germ cells were selectively and rapidly lost from mature, fertile testis (10 days). The amount of CGP and EGP subclasses decreased to similar extents. This was accompanied by a dramatic elimination of 22:5n-6 from all GPL, 20:4n-6 decreasing less, especially in the plasmalogens. The germ cell-lacking immature testis and the germ cell-depleted adult rat testis were both characterized by a low proportion of 22:5n-6 in all their GPL.