Correlation between sperm membrane destabilization by heparin and aniline blue staining as membrane integrity index

CALCIUM (HYDROGEN-1-MALATE) HEXAHYDRATE ONECHEVERIA GIBBIFLORALEAVES AND ITS EFFECT ON SPERM CELLS

Echeveria gibbiflora is a plant widely used for its contraceptive activity in traditional Mexican medicine. Data on calcium crystals in plants are not outstanding. In the case of the Echeveria gibbiflora leaves, however, its quality, quantity, and salt type are quite surprising; one striking result of its X-ray crystallographic data shows the presence of calcium bis (hydrogen-1-malate) hexahydrate [2(C4H5O(5)1), Ca(1)2+, 6(H2O1)]. This highly soluble compound might explain the rapid shape changes of calcium crystals. Because SEM-EDS analysis shows that calcium malate crystals were obtained in a highly pure state and the immobilization and agglutination pattern that OBACE show on human and bull spermatozoa are not found even when high concentrations of calcium bis (hydrogen-1-malate) hexahydrate salt are present it is not feasible to involucrate molecules as calcium malate as part of the OBACE contraceptive activity.

Heparin binding sites are present at a higher concentration on sperm of subfertile men than donors of known fertility

Heparin sulfate has been shown to both stimulate sperm capacitation and cause decondensation of sperm chromatin. Recent studies have shown that sperm chromatin decondensation following exposure to a low concentration of heparin sulfate is inversely correlated with penetration ability. This study shows that sperm from subfertile patients contain a higher (p < .05) concentration of heparin binding sites than sperm from donors of known fertility. No differences were observed in the binding affinity of 3H-labeled heparin to donor and patient sperm. Binding was specific for sulfated heparin and dextran. FITC-labeled heparin bound to a higher percentage (p < .01) of patient sperm (39.6 +/- 3.1) than donor sperm (12.3 +/- 1.7). A relationship is demonstrated between heparin binding sites and sperm chromatin decondensation following heparin cxposure, both of which are increased in sperm from subfertile men.

Nucleons, I: A model for studying the mechanism of sperm nucleus swelling in vitro

The nucleon, a highly organized chromatin structure, was studied to learn if its swelling takes place by the action of heparin/GSH, without the participation of any mechanism provided by sperm membranes, subcellular organelles, or other proteins foreign to the sperm nucleus. Sperm suspensions of guinea pigs and rats were incubated with 9 mM DTT and 1% CTAB. The nucleons obtained from washed epididymal spermatozoa appear under a phase-contrast microscope to preserve their original nucleus shape and to completely lack the acrosome, middle piece, and tail. In an electron microscope, nucleon thin sections show a slight nuclear chromatin decompressed from the periphery toward the center. An outstanding result was that the nucleon swelling pattern by heparin/GSH showed the same classic organization into hub-like nuclear bodies joined by a network of chromatin fibers ranging in thickness from 25 to 1.5 nm. Under the conditions of this study there was no need of any membrane or subcellular structure. At stage IV, all the thick fibers disappear, leaving only thin bead fibers on a string. With respect to nuclear swelling there is no doubt that the sperm chromatin is organized in a special form that decides a specific required pattern of unpacking.